Add dynamic tool search with native defer_loading for Anthropic/OpenAI (#30)

* Add dynamic tool search with native defer_loading for Anthropic/OpenAI

When MCP tools push the total tool count past a configurable threshold
(default 20), tool definitions are deferred to reduce token overhead and
improve tool selection accuracy. Three-tier approach mirrors the existing
web search pattern:

- Anthropic (Claude 4.x): native defer_loading + server-side BM25 search
- OpenAI (GPT-5.4+): native defer_loading + hosted search
- vLLM/llama/NIM: client-side BM25 fallback via synthetic tool_search tool

New module turnstone/core/tool_search.py with BM25Index (pure-Python,
zero deps) and ToolSearchManager (session-scoped visibility, expansion,
server hint generation). Discovered tools persist for the session lifetime
so the model only searches once per capability needed.

Config: [tools] search/search_threshold/search_max_results
CLI: --tool-search {auto,on,off}, --tool-search-threshold, --tool-search-max-results
Agents (plan/task) exempt — their scoped tool sets are always small.

43 new tests (1253 total). All diagrams regenerated with PlantUML 1.2025.2.

* Fix Copilot review feedback on tool search

- Fix _MCP_PREFIX_RE to handle underscores in server names (non-greedy match)
- Use ordered dict for _expanded to preserve tool discovery order
- Avoid constructing ToolSearchManager when below threshold in auto mode
- Return empty string from _mcp_server_summary when no servers (not "none")
- Fix CLI help text to reference threshold generically, not hardcoded "20"
- Fix agent exemption docs to accurately describe scoped tool sets
- Fix README to not hardcode "30+" threshold number
This commit is contained in:
Patrick Buckley
2026-03-08 01:43:38 -08:00
committed by GitHub
parent 14d57176ce
commit c7586abd0a
34 changed files with 1003 additions and 62 deletions
+8 -2
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@@ -11,7 +11,7 @@ Named after the [Ruddy Turnstone](https://en.wikipedia.org/wiki/Ruddy_turnstone)
## What it does
Turnstone gives LLMs tools — shell, files, search, web, planning — and orchestrates multi-turn conversations where the model investigates, acts, and reports. It runs as:
Turnstone gives LLMs tools — shell, files, search, web, planning — and orchestrates multi-turn conversations where the model investigates, acts, and reports. Native deferred tool loading for Anthropic and OpenAI APIs reduces token overhead and improves tool selection accuracy when MCP servers expose many tools; local models (vLLM, llama.cpp) get a transparent client-side BM25 fallback. It runs as:
- **Interactive sessions** — terminal CLI or browser UI with parallel workstreams
- **Queue-driven agents** — trigger workstreams via message queue, stream progress, approve or auto-approve tool use
@@ -151,7 +151,7 @@ Bridges BLPOP from their per-node queue (priority) then the shared queue. Direct
## Tools
14 built-in tools, 2 agent tools, plus external tools via MCP:
15 built-in tools, 2 agent tools, plus external tools via MCP:
| Tool | Description | Auto-approved |
|------|-------------|:---:|
@@ -167,10 +167,13 @@ Bridges BLPOP from their per-node queue (priority) then the shared queue. Direct
| `remember` | Save persistent facts | yes |
| `recall` | Search memories and history | yes |
| `forget` | Remove a memory | yes |
| `notify` | Send notifications to linked channels | yes |
| `task` | Spawn autonomous sub-agent | |
| `plan` | Explore codebase, write .plan.md | |
| `mcp__*` | External tools from MCP servers | |
When the total tool count exceeds a configurable threshold (default 20), MCP tools are automatically deferred using native `defer_loading` on Anthropic and OpenAI APIs, or a transparent client-side BM25 search for local models. The LLM discovers deferred tools on demand via a `tool_search` capability — no configuration needed beyond `--tool-search auto` (the default).
### MCP Tool Servers
Turnstone supports the [Model Context Protocol](https://modelcontextprotocol.io/) (MCP) for connecting external tool servers. MCP tools are discovered at startup, converted to OpenAI function-calling format, and merged with built-in tools. Each MCP tool is prefixed with `mcp__{server}__{tool}` to avoid name collisions.
@@ -248,6 +251,9 @@ agent_model = "" # model alias for plan/task sub-agents
[tools]
timeout = 30
skip_permissions = false
search = "auto" # "auto" (enable when >threshold tools), "on", "off"
search_threshold = 20 # min tools before tool search activates
search_max_results = 5 # max tools returned per search query
[server]
host = "0.0.0.0"
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@@ -43,6 +43,7 @@ turnstone/
workstream.py Parallel workstream manager (WorkstreamState, Workstream, WorkstreamManager)
tools.py Tool schema loader (JSON -> OpenAI function-calling format)
mcp_client.py MCPClientManager — MCP server connections, tool discovery, async-sync bridge
tool_search.py Dynamic tool search — BM25 index, session-scoped tool visibility
model_registry.py ModelRegistry — named model configs, lazy client creation, fallback routing
memory.py Persistence facade (delegates to storage backend)
storage/ Pluggable storage: StorageBackend protocol, SQLite + PostgreSQL
@@ -94,7 +95,7 @@ turnstone/
style.css Page-specific UI styles (dashboard layout, approval blocks)
app.js Page-specific client-side JavaScript (SSE, workstreams, markdown)
tools/
*.json 14 tool schemas (OpenAI function-calling format + turnstone metadata)
*.json 15 tool schemas (OpenAI function-calling format + turnstone metadata)
```
Both UIs share a common design system extracted into `turnstone/shared_static/`: design tokens, login overlay, toast notifications, theme toggle, keyboard shortcuts, and utility functions. Each UI imports `base.css` and the shared JS modules at `/shared/`, then adds only page-specific code at `/static/`.
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@@ -41,6 +41,7 @@ package "turnstone/core/" <<Rectangle>> {
component [healthcheck.py\nBackendHealthMonitor] as healthcheck <<core>>
component [ratelimit.py\nRateLimiter] as ratelimit <<core>>
component [mcp_client.py\nMCPClientManager] as mcp <<core>>
component [tool_search.py\nToolSearchManager, BM25] as toolsearch <<core>>
component [model_registry.py\nModelRegistry] as registry <<core>>
}
@@ -95,7 +96,7 @@ package "turnstone/sdk/" <<Rectangle>> {
' Tool schemas
package "turnstone/tools/" <<Rectangle>> {
component [*.json\n14 tool schemas] as schemas <<artifact>>
component [*.json\n15 tool schemas] as schemas <<artifact>>
}
' Entry point dependencies
@@ -136,6 +137,7 @@ session --> edit
session --> web
session --> healthcheck
session --> mcp : optional
session --> toolsearch : optional
session --> registry : optional
registry --> providers
healthcheck --> metrics
+23
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@@ -108,6 +108,7 @@ class "ModelCapabilities" as ModelCaps <<frozen>> {
+ thinking_mode: str
+ supports_effort: bool
+ supports_web_search: bool
+ supports_tool_search: bool
}
' ChatSession
@@ -120,6 +121,7 @@ class "ChatSession" as ChatSession {
- _msg_tokens: list[int]
- _ws_id: str
- _mcp_client: MCPClientManager | None
- _tool_search: ToolSearchManager | None
- _registry: ModelRegistry | None
+ model_alias: str | None {property}
- _tools: list[dict]
@@ -139,6 +141,9 @@ class "ChatSession" as ChatSession {
- _prepare_tool(tc) → item dict
- _prepare_mcp_tool(call_id, name, args) → item dict
- _exec_mcp_tool(item) → (call_id, output)
- _get_active_tools() → list[dict]
- _prepare_tool_search() → None
- _exec_tool_search(item) → (call_id, output)
- _run_agent(messages, tools, ...) → str
- _compact_messages(auto: bool)
- _full_messages() → list[dict]
@@ -217,6 +222,23 @@ class "MCPClientManager" as MCPMgr {
core/mcp_client.py
}
' ToolSearchManager
class "ToolSearchManager" as ToolSearchMgr {
- _all_tools: list[dict]
- _always_on: list[dict]
- _deferred: list[dict]
- _expanded: set[str]
- _index: BM25Index
--
+ should_activate() → bool
+ get_visible_tools() → list[dict]
+ get_deferred_tools() → list[dict]
+ search(query, k) → list[dict]
+ expand_visible(names) → list[dict]
+ get_search_tool_definition() → dict
+ format_search_results(tools) → str
}
' ModelRegistry
class "ModelRegistry" as ModelReg {
- _models: dict[str, ModelConfig]
@@ -317,6 +339,7 @@ LLMProvider <|.. AnthropicProv
ChatSession --> SessionUI : uses
ChatSession --> LLMProvider : delegates LLM calls
ChatSession --> MCPMgr : optional
ChatSession --o ToolSearchMgr : _tool_search
ChatSession --> ModelReg : optional
ChatSession <|-- HeadlessSession
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@@ -24,27 +24,29 @@ partition "Phase 1: Prepare" #E8F5E9 {
:Dispatch to _prepare_{func_name}();
note right
**Dispatch table (14 tools):**
┌─────────────┬──────────────────┐
│ Tool │ Needs Approval? │
├─────────────┼──────────────────┤
│ bash │ ✓ Yes │
│ read_file │ ✗ Auto-approve │
│ write_file │ ✓ Yes │
│ edit_file │ ✓ Yes │
│ search │ ✗ Auto-approve │
│ math │ ✓ Yes │
│ man │ ✗ Auto-approve │
│ web_fetch │ ✓ Yes │
│ web_search │ ✓ Yes │
│ task │ ✓ Yes
plan │ ✓ Yes │
remember │ ✗ Auto-approve
│ recall │ ✗ Auto-approve │
forget │ ✗ Auto-approve │
├─────────────┼──────────────────┤
mcp__*✓ Yes (external)
───────────────────────────────
**Dispatch table (16 tools):**
┌─────────────┬──────────────────┐
│ Tool │ Needs Approval? │
├─────────────┼──────────────────┤
│ bash │ ✓ Yes │
│ read_file │ ✗ Auto-approve │
│ write_file │ ✓ Yes │
│ edit_file │ ✓ Yes │
│ search │ ✗ Auto-approve │
│ math │ ✓ Yes │
│ man │ ✗ Auto-approve │
│ web_fetch │ ✓ Yes │
│ web_search │ ✓ Yes │
│ tool_search │ ✗ Auto-approve
task │ ✓ Yes │
plan │ ✓ Yes
│ remember │ ✗ Auto-approve │
recall │ ✗ Auto-approve │
│ forget │ ✗ Auto-approve │
notify ✗ Auto-approve
├────────────────────────────────
│ mcp__* │ ✓ Yes (external) │
└──────────────┴──────────────────┘
end note
:Build item dict:
@@ -106,8 +108,10 @@ partition "Phase 3: Execute" #E3F2FD {
├─ _exec_man: man/info subprocess
├─ _exec_web_fetch: httpx.get + LLM summary
├─ _exec_web_search: Tavily API POST (fallback for local models)
├─ _exec_tool_search: BM25 search + expand_visible()
├─ _exec_task: _run_agent(TASK_AGENT_TOOLS)
├─ _exec_plan: _run_agent(AGENT_TOOLS, read-only)
├─ _exec_notify: HTTP POST to channel gateway
├─ _exec_remember: SQLite INSERT OR REPLACE
├─ _exec_recall: SQLite FTS5/LIKE search
├─ _exec_forget: SQLite DELETE
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@@ -51,6 +51,7 @@ schema plus turnstone-specific metadata keys:
| `TASK_AGENT_TOOLS` | Tools with `task_agent: true` -- available to task sub-agents. Includes write operations. |
| `AGENT_AUTO_TOOLS` | Set of tool names with `auto_approve: true` -- no user confirmation needed. |
| `TASK_AUTO_TOOLS` | Same as `AGENT_AUTO_TOOLS` (identical filter). |
| `BUILTIN_TOOL_NAMES`| Frozenset of all 15 built-in tool names. Used by tool search to distinguish always-on tools from deferrable MCP tools. |
| `PRIMARY_KEY_MAP` | Dict mapping tool name to its `primary_key` parameter name. |
---
@@ -68,6 +69,9 @@ Tool execution follows a three-phase pipeline inside `ChatSession._execute_tools
- Parses the JSON arguments (with fallback for malformed JSON).
- If JSON parsing fails entirely, uses `PRIMARY_KEY_MAP` to map a bare string
to the correct parameter.
- Dispatches to the matching `_prepare_{func_name}()` handler. There are 15
built-in tools plus `tool_search` (synthetic, client-side BM25 fallback) and
the generic `_prepare_mcp_tool()` handler for MCP tools.
- Validates arguments and builds a preview dict containing:
- `call_id`, `func_name`, `header`, `preview` (for display)
- `needs_approval` (bool)
@@ -435,6 +439,77 @@ Provide either `username` for user-based targeting or `channel_type` +
| `recall` | Memory | Yes | No | No | `query` |
| `forget` | Memory | Yes | No | No | `key` |
| `notify` | Notify | Yes | Yes | Yes | `message` |
| `tool_search`| Search | Yes | No | No | `query` |
---
## Dynamic Tool Search
When many MCP tools are connected, the total tool count can grow large enough to
consume significant context window tokens and reduce model accuracy. Dynamic tool
search addresses this by deferring tools the model is unlikely to need on the
current turn and letting it search for them on demand.
### Three-tier approach
Tool search uses the best available mechanism for each provider:
1. **Anthropic (native)** -- Models that support it receive `defer_loading: true`
on deferred tool definitions plus the `tool_search_tool_bm25_20251119` server-side
search tool. Anthropic's API handles search and expansion transparently.
2. **OpenAI GPT-5.4+ (native)** -- Models with hosted tool search receive
`defer_loading: true` on deferred definitions. The API handles search internally.
3. **vLLM / llama.cpp / NIM (client-side BM25)** -- A synthetic `tool_search`
function tool is injected into the tool list. When the model calls it,
`_exec_tool_search()` runs a pure-Python BM25 index over tool names and
descriptions, then expands the matched tools into the visible set.
### Configuration
Tool search is configured in `config.toml` under the `[tools]` section:
```toml
[tools]
search = "auto" # "auto", "on", or "off"
search_threshold = 20 # minimum total tool count to activate
search_max_results = 5 # max tools returned per search call
```
CLI flags override the config file:
- `--tool-search {auto,on,off}` -- force tool search on or off, or let turnstone
decide based on threshold (default: `auto`).
- `--tool-search-threshold N` -- minimum tool count to activate (default: 20).
- `--tool-search-max-results N` -- max results per search (default: 5).
### How it works
1. **Threshold check**: At session startup, `ToolSearchManager.should_activate()`
counts total tools (built-in + MCP). If the count is below the threshold, tool
search stays off and all tools are sent to the model directly.
2. **Partitioning**: When active, tools are split into two sets:
- **Always-on** -- the 15 built-in tools (members of `BUILTIN_TOOL_NAMES`).
These are always visible to the model.
- **Deferred** -- all MCP tools. These are not sent in the tool list unless
the model searches for them.
3. **Search and expand**: When the model calls `tool_search` (client-side) or the
provider's native search returns results, the matched tools are added to the
visible set via `expand_visible()`. Once expanded, a tool stays visible for
the remainder of the session.
4. **Multi-turn persistence**: Expanded tools are never removed. This avoids
confusing the model when it references a tool it discovered in an earlier turn.
### Agent exemption
Plan and task sub-agents do not use tool search. They operate on scoped tool
sets (`AGENT_TOOLS` for plan agents, `TASK_AGENT_TOOLS` for task agents) with
MCP tools merged in. Tool search is only active for the top-level session,
where the model can interactively search for tools it needs.
---
@@ -456,8 +531,11 @@ MCP-compatible service.
3. **Schema conversion**: Each MCP tool's `inputSchema` is converted to OpenAI
function-calling format. The tool name is prefixed: `mcp__{server}__{tool}`.
4. **Merging**: MCP tools are appended after the 14 built-in tools via
4. **Merging**: MCP tools are appended after the 15 built-in tools via
`merge_mcp_tools()`. Built-in tools appear first, giving them natural LLM priority.
When dynamic tool search is active, MCP tools are deferred rather than directly
visible -- the model discovers them via search as needed (see
[Dynamic Tool Search](#dynamic-tool-search) above).
5. **Dispatch**: When the LLM calls an MCP tool, `_prepare_mcp_tool()` builds a
generic approval preview and `_exec_mcp_tool()` calls `MCPClientManager.call_tool_sync()`,
+116
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@@ -1933,3 +1933,119 @@ class TestAnthropicProviderBlocks:
assert blocks[1]["input"] == {"query": "test"} # parsed from accumulated JSON
assert blocks[2]["type"] == "web_search_tool_result"
assert blocks[2]["encrypted_content"] == "enc_data"
# ---------------------------------------------------------------------------
# Tool search tests
# ---------------------------------------------------------------------------
class TestAnthropicToolSearch:
"""Test Anthropic provider tool search injection."""
@pytest.fixture()
def provider(self):
from turnstone.core.providers._anthropic import AnthropicProvider
return AnthropicProvider()
def test_tool_search_capability_flag(self, provider):
caps = provider.get_capabilities("claude-opus-4-6-20260101")
assert caps.supports_tool_search is True
def test_tool_search_not_supported_on_haiku(self, provider):
caps = provider.get_capabilities("claude-haiku-4-5-20251001")
assert caps.supports_tool_search is False
def test_inject_tool_search_marks_deferred(self, provider):
caps = provider.get_capabilities("claude-opus-4-6-20260101")
tools = [
{"name": "bash", "description": "Run commands", "input_schema": {}},
{
"name": "mcp__github__create_issue",
"description": "Create issue",
"input_schema": {},
},
]
deferred = frozenset(["mcp__github__create_issue"])
result = provider._inject_tool_search(tools, caps, deferred)
# bash should not be deferred
assert result[0].get("defer_loading") is None or result[0].get("defer_loading") is False
# MCP tool should be deferred
assert result[1]["defer_loading"] is True
# Search tool should be appended
assert result[-1]["type"] == "tool_search_tool_bm25_20251119"
assert result[-1]["name"] == "tool_search"
def test_inject_tool_search_no_op_without_deferred(self, provider):
caps = provider.get_capabilities("claude-opus-4-6-20260101")
tools = [{"name": "bash", "description": "Run commands", "input_schema": {}}]
result = provider._inject_tool_search(tools, caps, None)
assert result == tools
def test_inject_tool_search_no_op_on_unsupported_model(self, provider):
caps = provider.get_capabilities("claude-haiku-4-5-20251001")
tools = [{"name": "bash", "description": "Run commands", "input_schema": {}}]
deferred = frozenset(["some_tool"])
result = provider._inject_tool_search(tools, caps, deferred)
assert result == tools
class TestOpenAIToolSearch:
"""Test OpenAI provider tool search injection."""
@pytest.fixture()
def provider(self):
return OpenAIProvider()
def test_tool_search_capability_on_gpt54(self, provider):
caps = provider.get_capabilities("gpt-5.4")
assert caps.supports_tool_search is True
def test_tool_search_not_supported_on_gpt5(self, provider):
caps = provider.get_capabilities("gpt-5")
assert caps.supports_tool_search is False
def test_apply_tool_search_marks_deferred(self, provider):
caps = provider.get_capabilities("gpt-5.4")
tools = [
{"type": "function", "function": {"name": "bash", "description": "Run commands"}},
{
"type": "function",
"function": {"name": "mcp__slack__send", "description": "Send message"},
},
]
deferred = frozenset(["mcp__slack__send"])
result = provider._apply_tool_search(caps, tools, deferred)
assert result is not None
# bash not deferred
assert result[0].get("defer_loading") is None or result[0].get("defer_loading") is False
# slack tool deferred
assert result[1]["defer_loading"] is True
def test_apply_tool_search_no_op_without_deferred(self, provider):
caps = provider.get_capabilities("gpt-5.4")
tools = [
{"type": "function", "function": {"name": "bash", "description": "Run commands"}},
]
result = provider._apply_tool_search(caps, tools, None)
assert result == tools
def test_apply_tool_search_no_op_on_unsupported_model(self, provider):
caps = provider.get_capabilities("gpt-5")
tools = [
{"type": "function", "function": {"name": "bash", "description": "Run commands"}},
]
deferred = frozenset(["some_tool"])
result = provider._apply_tool_search(caps, tools, deferred)
assert result == tools
class TestModelCapabilitiesToolSearch:
"""Test supports_tool_search defaults and values."""
def test_default_is_false(self):
from turnstone.core.providers._protocol import ModelCapabilities
caps = ModelCapabilities()
assert caps.supports_tool_search is False
+246
View File
@@ -0,0 +1,246 @@
"""Tests for turnstone.core.tool_search — BM25 index and tool search manager."""
from __future__ import annotations
import pytest
from turnstone.core.tool_search import (
BM25Index,
ToolSearchManager,
_mcp_server_summary,
_tokenize,
_tool_name,
)
# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------
def _make_tool(name: str, description: str = "") -> dict:
"""Create a minimal OpenAI-format tool dict for testing."""
return {
"type": "function",
"function": {
"name": name,
"description": description or f"Tool {name}",
"parameters": {"type": "object", "properties": {}},
},
}
# ---------------------------------------------------------------------------
# BM25Index tests
# ---------------------------------------------------------------------------
class TestTokenize:
def test_basic_split(self):
assert _tokenize("hello world") == ["hello", "world"]
def test_underscore_split(self):
assert _tokenize("create_issue") == ["create", "issue"]
def test_mixed_delimiters(self):
assert _tokenize("mcp__github__create-issue") == ["mcp", "github", "create", "issue"]
def test_empty_string(self):
assert _tokenize("") == []
def test_lowercased(self):
assert _tokenize("GitHub Create") == ["github", "create"]
class TestBM25Index:
def test_empty_corpus(self):
idx = BM25Index([])
assert idx.search("test") == []
def test_empty_query(self):
idx = BM25Index(["hello world", "foo bar"])
assert idx.search("") == []
def test_single_document(self):
idx = BM25Index(["create github issue"])
assert idx.search("github") == [0]
def test_ranking_order(self):
docs = [
"list_repos List all repositories",
"create_issue Create a new GitHub issue",
"get_issue Get details of a GitHub issue",
]
idx = BM25Index(docs)
results = idx.search("github issue")
# Both issue-related docs should rank above list_repos
assert 1 in results[:2]
assert 2 in results[:2]
def test_top_k_limit(self):
docs = [f"tool_{i} description {i}" for i in range(20)]
idx = BM25Index(docs)
results = idx.search("tool description", k=3)
assert len(results) <= 3
def test_no_match(self):
idx = BM25Index(["alpha beta gamma"])
assert idx.search("zzzzz") == []
def test_exact_name_match_ranks_high(self):
docs = [
"send_email Send an email message",
"send_slack Send a Slack message",
"read_email Read email inbox",
]
idx = BM25Index(docs)
results = idx.search("send email")
assert results[0] == 0 # send_email should rank first
# ---------------------------------------------------------------------------
# ToolSearchManager tests
# ---------------------------------------------------------------------------
class TestToolSearchManager:
@pytest.fixture()
def builtin_tools(self):
return [
_make_tool("bash", "Execute shell commands"),
_make_tool("read_file", "Read a file"),
_make_tool("edit_file", "Edit a file"),
]
@pytest.fixture()
def mcp_tools(self):
return [
_make_tool("mcp__github__create_issue", "Create a new GitHub issue"),
_make_tool("mcp__github__list_issues", "List GitHub issues"),
_make_tool("mcp__github__get_repo", "Get repository details"),
_make_tool("mcp__slack__send_message", "Send a Slack message"),
_make_tool("mcp__slack__list_channels", "List Slack channels"),
_make_tool("mcp__jira__create_ticket", "Create a Jira ticket"),
]
@pytest.fixture()
def manager(self, builtin_tools, mcp_tools):
all_tools = builtin_tools + mcp_tools
return ToolSearchManager(
all_tools,
always_on_names={"bash", "read_file", "edit_file"},
threshold=5,
max_results=3,
)
def test_should_activate_above_threshold(self, manager):
assert manager.should_activate()
def test_should_not_activate_below_threshold(self, builtin_tools):
mgr = ToolSearchManager(builtin_tools, always_on_names={"bash", "read_file", "edit_file"})
assert not mgr.should_activate()
def test_visible_tools_initially_builtin_only(self, manager):
visible = manager.get_visible_tools()
names = {_tool_name(t) for t in visible}
assert names == {"bash", "read_file", "edit_file"}
def test_deferred_tools_excludes_builtin(self, manager):
deferred = manager.get_deferred_tools()
names = {_tool_name(t) for t in deferred}
assert "bash" not in names
assert "mcp__github__create_issue" in names
def test_search_returns_relevant_tools(self, manager):
results = manager.search("github issue")
names = {_tool_name(t) for t in results}
assert "mcp__github__create_issue" in names or "mcp__github__list_issues" in names
def test_search_respects_max_results(self, manager):
results = manager.search("tool")
assert len(results) <= 3
def test_search_excludes_already_expanded(self, manager):
# Expand a github tool, then search for github — expanded tool should not appear
manager.expand_visible(["mcp__github__create_issue"])
results = manager.search("github issue")
names = {_tool_name(t) for t in results}
assert "mcp__github__create_issue" not in names
def test_expand_visible_adds_tools(self, manager):
manager.expand_visible(["mcp__github__create_issue"])
visible = manager.get_visible_tools()
names = {_tool_name(t) for t in visible}
assert "mcp__github__create_issue" in names
def test_expand_visible_returns_newly_added(self, manager):
added = manager.expand_visible(["mcp__github__create_issue", "mcp__slack__send_message"])
assert len(added) == 2
names = {_tool_name(t) for t in added}
assert names == {"mcp__github__create_issue", "mcp__slack__send_message"}
def test_expand_visible_idempotent(self, manager):
manager.expand_visible(["mcp__github__create_issue"])
added = manager.expand_visible(["mcp__github__create_issue"])
assert added == []
def test_expand_visible_ignores_unknown(self, manager):
added = manager.expand_visible(["nonexistent_tool"])
assert added == []
def test_deferred_excludes_expanded(self, manager):
manager.expand_visible(["mcp__github__create_issue"])
deferred = manager.get_deferred_tools()
names = {_tool_name(t) for t in deferred}
assert "mcp__github__create_issue" not in names
def test_get_all_tools_returns_everything(self, manager, builtin_tools, mcp_tools):
assert len(manager.get_all_tools()) == len(builtin_tools) + len(mcp_tools)
def test_search_tool_definition_format(self, manager):
defn = manager.get_search_tool_definition()
assert defn["type"] == "function"
fn = defn["function"]
assert fn["name"] == "tool_search"
assert "query" in fn["parameters"]["properties"]
assert "query" in fn["parameters"]["required"]
def test_search_tool_description_has_server_hint(self, manager):
defn = manager.get_search_tool_definition()
desc = defn["function"]["description"]
assert "github" in desc
assert "slack" in desc
assert "jira" in desc
def test_format_search_results_empty(self, manager):
text = manager.format_search_results([])
assert "No matching tools found" in text
def test_format_search_results_with_tools(self, manager, mcp_tools):
text = manager.format_search_results(mcp_tools[:2])
assert "Found 2" in text
assert "mcp__github__create_issue" in text
# ---------------------------------------------------------------------------
# Helper function tests
# ---------------------------------------------------------------------------
class TestMCPServerSummary:
def test_groups_by_server(self):
tools = [
_make_tool("mcp__github__a"),
_make_tool("mcp__github__b"),
_make_tool("mcp__slack__c"),
]
summary = _mcp_server_summary(tools)
assert "github (2 tools)" in summary
assert "slack (1 tool)" in summary
def test_non_mcp_tools_counted_as_other(self):
tools = [_make_tool("custom_tool")]
summary = _mcp_server_summary(tools)
assert "other (1 tool)" in summary
def test_empty_list(self):
assert _mcp_server_summary([]) == ""
+21
View File
@@ -784,6 +784,24 @@ def main() -> None:
default=0,
help="Tool output truncation limit in chars, 0 for auto (50%% of context window) (default: 0)",
)
parser.add_argument(
"--tool-search",
choices=["auto", "on", "off"],
default="auto",
help="Dynamic tool search: auto (enable when tool count exceeds threshold), on, off (default: auto)",
)
parser.add_argument(
"--tool-search-threshold",
type=int,
default=20,
help="Min tools before tool search activates (default: 20)",
)
parser.add_argument(
"--tool-search-max-results",
type=int,
default=5,
help="Max tools returned per tool search query (default: 5)",
)
parser.add_argument(
"--resume",
default=None,
@@ -917,6 +935,9 @@ def main() -> None:
mcp_client=mcp_client,
registry=registry,
model_alias=model_alias or registry.default,
tool_search=args.tool_search,
tool_search_threshold=args.tool_search_threshold,
tool_search_max_results=args.tool_search_max_results,
)
# Create workstream manager and initial workstream
+3
View File
@@ -70,6 +70,9 @@ _CONFIG_MAP: dict[str, dict[str, str]] = {
"truncation": "tool_truncation",
"agent_max_turns": "agent_max_turns",
"skip_permissions": "skip_permissions",
"search": "tool_search",
"search_threshold": "tool_search_threshold",
"search_max_results": "tool_search_max_results",
},
"server": {
"host": "host",
+38
View File
@@ -64,6 +64,9 @@ def _merge_consecutive(messages: list[dict[str, Any]]) -> list[dict[str, Any]]:
# Tool version for Anthropic's server-side web search (update when new version ships)
_WEB_SEARCH_TOOL_TYPE = "web_search_20250305"
# Tool search: server-side BM25 tool discovery for deferred tools
_TOOL_SEARCH_TOOL_TYPE = "tool_search_tool_bm25_20251119"
# -- model capabilities -------------------------------------------------------
_ANTHROPIC_DEFAULT = ModelCapabilities(
@@ -83,6 +86,7 @@ _ANTHROPIC_CAPABILITIES: dict[str, ModelCapabilities] = {
supports_effort=True,
effort_levels=("low", "medium", "high", "max"),
supports_web_search=True,
supports_tool_search=True,
),
"claude-sonnet-4-6": ModelCapabilities(
context_window=200000,
@@ -92,6 +96,7 @@ _ANTHROPIC_CAPABILITIES: dict[str, ModelCapabilities] = {
supports_effort=True,
effort_levels=("low", "medium", "high"),
supports_web_search=True,
supports_tool_search=True,
),
"claude-haiku-4-5": ModelCapabilities(
context_window=200000,
@@ -122,6 +127,7 @@ _ANTHROPIC_CAPABILITIES: dict[str, ModelCapabilities] = {
token_param="max_tokens",
thinking_mode="manual",
supports_web_search=True,
supports_tool_search=True,
),
"claude-sonnet-4": ModelCapabilities(
context_window=200000,
@@ -129,6 +135,7 @@ _ANTHROPIC_CAPABILITIES: dict[str, ModelCapabilities] = {
token_param="max_tokens",
thinking_mode="manual",
supports_web_search=True,
supports_tool_search=True,
),
}
@@ -182,6 +189,31 @@ class AnthropicProvider:
filtered.append({"type": _WEB_SEARCH_TOOL_TYPE, "name": "web_search"})
return filtered
# -- tool search injection -----------------------------------------------
def _inject_tool_search(
self,
tools: list[dict[str, Any]],
caps: ModelCapabilities,
deferred_names: frozenset[str] | None = None,
) -> list[dict[str, Any]]:
"""Mark deferred tools and add native server-side search tool.
When the model supports tool search and ``deferred_names`` is provided,
tools whose name is in the deferred set get ``defer_loading: true``.
The BM25 search tool is appended so the model can discover them.
"""
if not caps.supports_tool_search or not deferred_names:
return tools
result = []
for tool in tools:
if tool.get("name", "") in deferred_names:
result.append({**tool, "defer_loading": True})
else:
result.append(tool)
result.append({"type": _TOOL_SEARCH_TOOL_TYPE, "name": "tool_search"})
return result
# -- shared param logic --------------------------------------------------
def _build_thinking_and_kwargs(
@@ -195,6 +227,7 @@ class AnthropicProvider:
system_prompt: str,
model: str,
tools: list[dict[str, Any]] | None,
deferred_names: frozenset[str] | None = None,
) -> dict[str, Any]:
"""Build the full kwargs dict with thinking mode and effort params."""
thinking_params: dict[str, Any] = {}
@@ -217,6 +250,7 @@ class AnthropicProvider:
if tools:
anthropic_tools = self.convert_tools(tools)
anthropic_tools = self._inject_web_search(anthropic_tools, caps)
anthropic_tools = self._inject_tool_search(anthropic_tools, caps, deferred_names)
kwargs["tools"] = anthropic_tools
kwargs.update(thinking_params)
@@ -371,6 +405,7 @@ class AnthropicProvider:
temperature: float = 0.5,
reasoning_effort: str = "medium",
extra_params: dict[str, Any] | None = None,
deferred_names: frozenset[str] | None = None,
) -> Iterator[StreamChunk]:
_ensure_anthropic()
caps = self.get_capabilities(model)
@@ -385,6 +420,7 @@ class AnthropicProvider:
system_prompt,
model,
tools,
deferred_names,
)
with client.messages.stream(**kwargs) as stream:
@@ -536,6 +572,7 @@ class AnthropicProvider:
temperature: float = 0.5,
reasoning_effort: str = "medium",
extra_params: dict[str, Any] | None = None,
deferred_names: frozenset[str] | None = None,
) -> CompletionResult:
_ensure_anthropic()
caps = self.get_capabilities(model)
@@ -550,6 +587,7 @@ class AnthropicProvider:
system_prompt,
model,
tools,
deferred_names,
)
response = client.messages.create(**kwargs)
+32 -2
View File
@@ -82,20 +82,22 @@ _OPENAI_CAPABILITIES: dict[str, ModelCapabilities] = {
reasoning_effort_values=("none", "low", "medium", "high", "xhigh"),
default_reasoning_effort="none",
),
# GPT-5.4 — 1M context window
# GPT-5.4 — 1M context window, native tool search
"gpt-5.4": ModelCapabilities(
context_window=1050000,
max_output_tokens=128000,
reasoning_effort_values=("none", "low", "medium", "high", "xhigh"),
default_reasoning_effort="none",
supports_tool_search=True,
),
# GPT-5.4 pro — always-reasoning, 1M context
# GPT-5.4 pro — always-reasoning, 1M context, native tool search
"gpt-5.4-pro": ModelCapabilities(
context_window=1050000,
max_output_tokens=128000,
supports_temperature=False,
reasoning_effort_values=("medium", "high", "xhigh"),
default_reasoning_effort="medium",
supports_tool_search=True,
),
# O-series reasoning models
"o1": ModelCapabilities(
@@ -215,6 +217,30 @@ class OpenAIProvider:
kwargs["web_search_options"] = {}
return tools
# -- tool search ---------------------------------------------------------
def _apply_tool_search(
self,
caps: ModelCapabilities,
tools: list[dict[str, Any]] | None,
deferred_names: frozenset[str] | None = None,
) -> list[dict[str, Any]] | None:
"""Mark deferred tools with ``defer_loading: true`` for native search.
For GPT-5.4+ models that support tool search, OpenAI's API handles
discovery automatically — no explicit search tool is needed.
"""
if not caps.supports_tool_search or not deferred_names or not tools:
return tools
result = []
for tool in tools:
name = tool.get("function", {}).get("name", "")
if name in deferred_names:
result.append({**tool, "defer_loading": True})
else:
result.append(tool)
return result
# -- streaming -----------------------------------------------------------
def create_streaming(
@@ -228,6 +254,7 @@ class OpenAIProvider:
temperature: float = 0.5,
reasoning_effort: str = "medium",
extra_params: dict[str, Any] | None = None,
deferred_names: frozenset[str] | None = None,
) -> Iterator[StreamChunk]:
caps = self.get_capabilities(model)
kwargs: dict[str, Any] = {
@@ -239,6 +266,7 @@ class OpenAIProvider:
}
self._apply_model_params(kwargs, caps, temperature, reasoning_effort)
tools = self._apply_web_search(kwargs, caps, tools)
tools = self._apply_tool_search(caps, tools, deferred_names)
if tools:
kwargs["tools"] = tools
if extra_params:
@@ -332,6 +360,7 @@ class OpenAIProvider:
temperature: float = 0.5,
reasoning_effort: str = "medium",
extra_params: dict[str, Any] | None = None,
deferred_names: frozenset[str] | None = None,
) -> CompletionResult:
caps = self.get_capabilities(model)
kwargs: dict[str, Any] = {
@@ -342,6 +371,7 @@ class OpenAIProvider:
}
self._apply_model_params(kwargs, caps, temperature, reasoning_effort)
tools = self._apply_web_search(kwargs, caps, tools)
tools = self._apply_tool_search(caps, tools, deferred_names)
if tools:
kwargs["tools"] = tools
if extra_params:
+3
View File
@@ -76,6 +76,7 @@ class ModelCapabilities:
reasoning_effort_values: tuple[str, ...] = ()
default_reasoning_effort: str = "medium"
supports_web_search: bool = False
supports_tool_search: bool = False
def _lookup_capabilities(
@@ -119,6 +120,7 @@ class LLMProvider(Protocol):
temperature: float = 0.5,
reasoning_effort: str = "medium",
extra_params: dict[str, Any] | None = None,
deferred_names: frozenset[str] | None = None,
) -> Iterator[StreamChunk]:
"""Create a streaming request, yielding normalized StreamChunks."""
...
@@ -134,6 +136,7 @@ class LLMProvider(Protocol):
temperature: float = 0.5,
reasoning_effort: str = "medium",
extra_params: dict[str, Any] | None = None,
deferred_names: frozenset[str] | None = None,
) -> CompletionResult:
"""Create a non-streaming request, returning a normalized result."""
...
+108 -3
View File
@@ -50,9 +50,11 @@ from turnstone.core.providers import create_provider
from turnstone.core.safety import is_command_blocked, sanitize_command
from turnstone.core.sandbox import execute_math_sandboxed
from turnstone.core.storage._registry import get_storage
from turnstone.core.tool_search import ToolSearchManager
from turnstone.core.tools import (
AGENT_AUTO_TOOLS,
AGENT_TOOLS,
BUILTIN_TOOL_NAMES,
PRIMARY_KEY_MAP,
TASK_AGENT_TOOLS,
TASK_AUTO_TOOLS,
@@ -158,6 +160,9 @@ class ChatSession:
health_monitor: BackendHealthMonitor | None = None,
node_id: str | None = None,
ws_id: str | None = None,
tool_search: str = "auto",
tool_search_threshold: int = 20,
tool_search_max_results: int = 5,
):
self.client = client
self.model = model
@@ -212,6 +217,17 @@ class ChatSession:
self._tools = TOOLS
self._task_tools = TASK_AGENT_TOOLS
self._agent_tools = AGENT_TOOLS
# Dynamic tool search: defer MCP tools when tool count is high
self._tool_search: ToolSearchManager | None = None
if tool_search == "on" or (
tool_search == "auto" and len(self._tools) > tool_search_threshold
):
self._tool_search = ToolSearchManager(
self._tools,
always_on_names=set(BUILTIN_TOOL_NAMES),
threshold=tool_search_threshold,
max_results=tool_search_max_results,
)
self._init_system_messages()
self._save_config()
@@ -393,6 +409,14 @@ class ChatSession:
"Look up documentation → man:\n"
" man(page='tar')",
]
# Tool search hint (client-side mode only — native mode needs no hint)
if self._tool_search:
caps = self._provider.get_capabilities(self.model)
if not caps.supports_tool_search:
dev_parts.append(
"\n\nAdditional tools are available via tool_search. "
"Use it when you need a capability not in your current tool set."
)
if self.instructions:
dev_parts.append("")
dev_parts.append(self.instructions)
@@ -429,6 +453,41 @@ class ChatSession:
return {"chat_template_kwargs": kwargs}
return None
# -- tool search helpers --------------------------------------------------
def _get_active_tools(self) -> list[dict[str, Any]] | None:
"""Return the tool list to send to the LLM.
When tool search is active:
- Native mode (provider supports it): send all tools (provider
marks deferred ones with defer_loading).
- Client-side fallback: send visible tools + synthetic tool_search.
Without tool search: return self._tools unchanged.
"""
if self.creative_mode:
return None
if not self._tool_search:
return self._tools
# Check if provider supports native tool search
caps = self._provider.get_capabilities(self.model)
if caps.supports_tool_search:
# Provider handles defer_loading — send all tools
return self._tools
# Client-side fallback: visible tools + search tool
visible = self._tool_search.get_visible_tools()
return visible + [self._tool_search.get_search_tool_definition()]
def _get_deferred_names(self) -> frozenset[str] | None:
"""Return names of deferred tools for native provider search, or None."""
if not self._tool_search:
return None
caps = self._provider.get_capabilities(self.model)
if not caps.supports_tool_search:
return None # Client-side mode — no deferred names for provider
deferred = self._tool_search.get_deferred_tools()
return frozenset(name for t in deferred if (name := t.get("function", {}).get("name", "")))
# Retryable error names are now provided by LLMProvider.retryable_error_names.
_MAX_RETRIES = 3
_RETRY_BASE_DELAY = 1.0 # seconds
@@ -488,11 +547,12 @@ class ChatSession:
client=client,
model=model,
messages=msgs,
tools=self._tools if not self.creative_mode else None,
tools=self._get_active_tools(),
max_tokens=self.max_tokens,
temperature=self.temperature,
reasoning_effort=self.reasoning_effort,
extra_params=self._provider_extra_params(provider=prov),
deferred_names=self._get_deferred_names(),
)
except Exception as e:
ename = type(e).__name__
@@ -883,7 +943,8 @@ class ChatSession:
f"{GRAY}[request] model={self.model} "
f"max_tokens={self.max_tokens} temp={self.temperature} "
f"reasoning={self.reasoning_effort} "
f"tools={0 if self.creative_mode else len(self._tools)}{RESET}"
f"tools={0 if self.creative_mode else len(self._get_active_tools() or [])}"
f"{' (search)' if self._tool_search else ''}{RESET}"
)
lines.append(f"{GRAY}[request] {len(msgs)} messages:{RESET}")
for i, m in enumerate(msgs):
@@ -937,7 +998,8 @@ class ChatSession:
# Calibrate chars_per_token ratio from actual usage.
all_msgs = self._full_messages() # system + self.messages (before append)
tool_def_chars = sum(len(json.dumps(t)) for t in self._tools)
active_tools = self._get_active_tools() or []
tool_def_chars = sum(len(json.dumps(t)) for t in active_tools)
total_chars = sum(self._msg_char_count(m) for m in all_msgs) + tool_def_chars
if total_chars > 0 and prompt_tok > 0:
self._chars_per_token = total_chars / prompt_tok
@@ -1281,6 +1343,7 @@ class ChatSession:
"man": self._prepare_man,
"web_fetch": self._prepare_web_fetch,
"web_search": self._prepare_web_search,
"tool_search": self._prepare_tool_search,
"task": self._prepare_task,
"plan": self._prepare_plan,
"remember": self._prepare_remember,
@@ -1763,6 +1826,48 @@ class ChatSession:
"topic": topic,
}
def _prepare_tool_search(self, call_id: str, args: dict[str, Any]) -> dict[str, Any]:
"""Prepare a tool search query (client-side BM25 fallback)."""
query = (args.get("query") or "").strip()
if not query:
return {
"call_id": call_id,
"func_name": "tool_search",
"header": "\u2717 tool_search: empty query",
"preview": "",
"needs_approval": False,
"error": "Error: no query provided",
}
if not self._tool_search:
return {
"call_id": call_id,
"func_name": "tool_search",
"header": "\u2717 tool_search: not active",
"preview": "",
"needs_approval": False,
"error": "Tool search is not active.",
}
return {
"call_id": call_id,
"func_name": "tool_search",
"header": f"\u2699 tool_search: {query[:80]}",
"preview": f" {DIM}{query}{RESET}",
"needs_approval": False,
"execute": self._exec_tool_search,
"query": query,
}
def _exec_tool_search(self, item: dict[str, Any]) -> tuple[str, str]:
"""Execute a client-side tool search and expand visible tools."""
assert self._tool_search is not None
query = item["query"]
results = self._tool_search.search(query)
# Expand discovered tools into the visible set
names = [t.get("function", {}).get("name", "") for t in results]
self._tool_search.expand_visible(names)
output = self._tool_search.format_search_results(results)
return item["call_id"], output
def _prepare_task(self, call_id: str, args: dict[str, Any]) -> dict[str, Any]:
"""Prepare a general-purpose sub-agent task for approval."""
prompt = (args.get("prompt") or "").strip()
+243
View File
@@ -0,0 +1,243 @@
"""Dynamic tool search — BM25 index and session-scoped visibility manager.
When the total tool count exceeds a configurable threshold, deferred tools
are hidden from the LLM and discoverable via a ``tool_search`` function.
Native providers (Anthropic, OpenAI) handle search server-side; local
models (vLLM, llama.cpp) use the client-side BM25 fallback here.
"""
from __future__ import annotations
import math
import re
from collections import Counter
from typing import Any
# ---------------------------------------------------------------------------
# BM25 index — lightweight, pure-Python, zero external deps
# ---------------------------------------------------------------------------
_SPLIT_RE = re.compile(r"[_\-./\s]+")
def _tokenize(text: str) -> list[str]:
"""Split text on whitespace, underscores, hyphens, dots."""
return [t.lower() for t in _SPLIT_RE.split(text) if t]
class BM25Index:
"""Okapi BM25 index over tool name + description text."""
def __init__(self, documents: list[str], *, k1: float = 1.5, b: float = 0.75) -> None:
self.k1 = k1
self.b = b
self._docs = documents
self._doc_tokens: list[list[str]] = [_tokenize(d) for d in documents]
self._doc_lens = [len(t) for t in self._doc_tokens]
self._avgdl = sum(self._doc_lens) / max(len(self._doc_lens), 1)
self._n = len(documents)
# Document frequency per term
self._df: Counter[str] = Counter()
for tokens in self._doc_tokens:
for term in set(tokens):
self._df[term] += 1
def search(self, query: str, k: int = 5) -> list[int]:
"""Return indices of top-k documents sorted by descending BM25 score."""
q_tokens = _tokenize(query)
if not q_tokens:
return []
scores: list[tuple[float, int]] = []
for idx, doc_tokens in enumerate(self._doc_tokens):
score = self._score(q_tokens, doc_tokens, self._doc_lens[idx])
if score > 0:
scores.append((score, idx))
scores.sort(key=lambda x: (-x[0], x[1]))
return [idx for _, idx in scores[:k]]
def _score(self, q_tokens: list[str], doc_tokens: list[str], dl: int) -> float:
tf_map: Counter[str] = Counter(doc_tokens)
score = 0.0
for term in q_tokens:
if term not in tf_map:
continue
tf = tf_map[term]
df = self._df.get(term, 0)
idf = math.log((self._n - df + 0.5) / (df + 0.5) + 1.0)
numerator = tf * (self.k1 + 1)
denominator = tf + self.k1 * (1 - self.b + self.b * dl / self._avgdl)
score += idf * numerator / denominator
return score
# ---------------------------------------------------------------------------
# Tool search manager — partitions tools, tracks visibility
# ---------------------------------------------------------------------------
_MCP_PREFIX_RE = re.compile(r"^mcp__(.+?)__")
def _tool_name(tool: dict[str, Any]) -> str:
"""Extract function name from an OpenAI-format tool dict."""
fn: dict[str, Any] = tool.get("function", {})
name: str = fn.get("name", "")
return name
def _tool_text(tool: dict[str, Any]) -> str:
"""Build searchable text from tool name + description."""
fn = tool.get("function", {})
return f"{fn.get('name', '')} {fn.get('description', '')}"
def _mcp_server_summary(tools: list[dict[str, Any]]) -> str:
"""Summarise deferred tools by MCP server prefix for the hint."""
servers: Counter[str] = Counter()
other = 0
for tool in tools:
name = _tool_name(tool)
m = _MCP_PREFIX_RE.match(name)
if m:
servers[m.group(1)] += 1
else:
other += 1
parts = [f"{srv} ({cnt} tool{'s' if cnt != 1 else ''})" for srv, cnt in sorted(servers.items())]
if other:
parts.append(f"other ({other} tool{'s' if other != 1 else ''})")
return ", ".join(parts)
class ToolSearchManager:
"""Session-scoped tool visibility manager with BM25 search.
Partitions tools into always-on (built-in) and deferred (MCP) sets.
Tracks which deferred tools have been discovered and expanded into
the visible set for the current session.
"""
def __init__(
self,
all_tools: list[dict[str, Any]],
always_on_names: set[str],
*,
threshold: int = 20,
max_results: int = 5,
) -> None:
self._all_tools = all_tools
self._always_on: list[dict[str, Any]] = []
self._deferred: list[dict[str, Any]] = []
self._deferred_by_name: dict[str, dict[str, Any]] = {}
self._expanded: dict[str, None] = {} # ordered set (preserves discovery order)
self._threshold = threshold
self._max_results = max_results
for tool in all_tools:
name = _tool_name(tool)
if name in always_on_names:
self._always_on.append(tool)
else:
self._deferred.append(tool)
self._deferred_by_name[name] = tool
# BM25 index over deferred tools
texts = [_tool_text(t) for t in self._deferred]
self._index = BM25Index(texts)
# Pre-compute server summary for the search tool description
self._server_hint = _mcp_server_summary(self._deferred)
def should_activate(self) -> bool:
"""Return True if tool search should be active (enough tools)."""
return len(self._all_tools) > self._threshold
def get_visible_tools(self) -> list[dict[str, Any]]:
"""Return always-on tools + any expanded (discovered) tools."""
result = list(self._always_on)
for name in self._expanded:
tool = self._deferred_by_name.get(name)
if tool:
result.append(tool)
return result
def get_deferred_tools(self) -> list[dict[str, Any]]:
"""Return tools that are currently deferred (not yet discovered)."""
return [t for t in self._deferred if _tool_name(t) not in self._expanded]
def get_all_tools(self) -> list[dict[str, Any]]:
"""Return the full tool list (for native provider modes)."""
return list(self._all_tools)
def search(self, query: str) -> list[dict[str, Any]]:
"""Search deferred tools by query, return top-k matches.
Already-expanded tools are excluded so every result is genuinely new.
"""
# Request extra results to compensate for filtering out expanded tools
indices = self._index.search(query, k=self._max_results + len(self._expanded))
results = []
for i in indices:
if _tool_name(self._deferred[i]) not in self._expanded:
results.append(self._deferred[i])
if len(results) >= self._max_results:
break
return results
def expand_visible(self, tool_names: list[str]) -> list[dict[str, Any]]:
"""Promote discovered tools to the visible set.
Returns the newly-expanded tool definitions (excludes tools
that were already visible).
"""
newly_added = []
for name in tool_names:
if name not in self._expanded and name in self._deferred_by_name:
self._expanded[name] = None
newly_added.append(self._deferred_by_name[name])
return newly_added
def get_search_tool_definition(self) -> dict[str, Any]:
"""Return the synthetic ``tool_search`` function tool definition.
The description includes a dynamic hint listing available MCP
server names and tool counts so the model can craft specific queries.
"""
desc = (
"Search for available tools by keyword. Returns matching tool "
"names and descriptions. Use this when you need a capability "
"not available in your current tool set."
)
if self._server_hint:
desc += f" Available tool servers: {self._server_hint}."
return {
"type": "function",
"function": {
"name": "tool_search",
"description": desc,
"parameters": {
"type": "object",
"properties": {
"query": {
"type": "string",
"description": "Search query describing the capability you need.",
},
},
"required": ["query"],
},
},
}
def format_search_results(self, tools: list[dict[str, Any]]) -> str:
"""Format search results as text for the tool_search response."""
if not tools:
return "No matching tools found. Try a different search query."
lines = []
for tool in tools:
fn = tool.get("function", {})
name = fn.get("name", "")
desc = fn.get("description", "")
lines.append(f"- **{name}**: {desc}")
return (
f"Found {len(tools)} matching tool(s):\n"
+ "\n".join(lines)
+ "\n\nThese tools are now available for use."
)
+1
View File
@@ -37,6 +37,7 @@ TASK_AGENT_TOOLS = [t for t in TOOLS if _META[t["function"]["name"]].get("task_a
AGENT_AUTO_TOOLS = {n for n, m in _META.items() if m.get("auto_approve")}
TASK_AUTO_TOOLS = {n for n, m in _META.items() if m.get("auto_approve")}
PRIMARY_KEY_MAP = {n: m["primary_key"] for n, m in _META.items() if "primary_key" in m}
BUILTIN_TOOL_NAMES = frozenset(_META)
def merge_mcp_tools(
+21
View File
@@ -1212,6 +1212,24 @@ def main() -> None:
default=0,
help="Tool output truncation limit in chars, 0 for auto (50%% of context window) (default: 0)",
)
parser.add_argument(
"--tool-search",
choices=["auto", "on", "off"],
default="auto",
help="Dynamic tool search: auto (enable when tool count exceeds threshold), on, off (default: auto)",
)
parser.add_argument(
"--tool-search-threshold",
type=int,
default=20,
help="Min tools before tool search activates (default: 20)",
)
parser.add_argument(
"--tool-search-max-results",
type=int,
default=5,
help="Max tools returned per tool search query (default: 5)",
)
parser.add_argument(
"--resume",
default=None,
@@ -1462,6 +1480,9 @@ def main() -> None:
health_monitor=health_monitor,
node_id=_node_id,
ws_id=ws_id,
tool_search=args.tool_search,
tool_search_threshold=args.tool_search_threshold,
tool_search_max_results=args.tool_search_max_results,
)
# Create workstream manager and initial workstream