π File detail
tools/ToolSearchTool/prompt.ts
π― Use case
This module implements the βToolSearchToolβ tool (Tool Search) β something the model can call at runtime alongside other agent tools. On the API surface it exposes isDeferredTool, formatDeferredToolLine, getPrompt, and TOOL_SEARCH_TOOL_NAME β mainly functions, hooks, or classes. Dependencies touch bun:bundle. It composes internal code from bootstrap, services, Tool, AgentTool, and constants (relative imports).
Generated from folder role, exports, dependency roots, and inline comments β not hand-reviewed for every path.
π§ Inline summary
import { feature } from 'bun:bundle' import { isReplBridgeActive } from '../../bootstrap/state.js' import { getFeatureValue_CACHED_MAY_BE_STALE } from '../../services/analytics/growthbook.js' import type { Tool } from '../../Tool.js' import { AGENT_TOOL_NAME } from '../AgentTool/constants.js'
π€ Exports (heuristic)
isDeferredToolformatDeferredToolLinegetPromptTOOL_SEARCH_TOOL_NAME
π External import roots
Package roots from from "β¦" (relative paths omitted).
bun:bundle
π₯οΈ Source preview
import { feature } from 'bun:bundle'
import { isReplBridgeActive } from '../../bootstrap/state.js'
import { getFeatureValue_CACHED_MAY_BE_STALE } from '../../services/analytics/growthbook.js'
import type { Tool } from '../../Tool.js'
import { AGENT_TOOL_NAME } from '../AgentTool/constants.js'
// Dead code elimination: Brief tool name only needed when KAIROS or KAIROS_BRIEF is on
/* eslint-disable @typescript-eslint/no-require-imports */
const BRIEF_TOOL_NAME: string | null =
feature('KAIROS') || feature('KAIROS_BRIEF')
? (
require('../BriefTool/prompt.js') as typeof import('../BriefTool/prompt.js')
).BRIEF_TOOL_NAME
: null
const SEND_USER_FILE_TOOL_NAME: string | null = feature('KAIROS')
? (
require('../SendUserFileTool/prompt.js') as typeof import('../SendUserFileTool/prompt.js')
).SEND_USER_FILE_TOOL_NAME
: null
/* eslint-enable @typescript-eslint/no-require-imports */
export { TOOL_SEARCH_TOOL_NAME } from './constants.js'
import { TOOL_SEARCH_TOOL_NAME } from './constants.js'
const PROMPT_HEAD = `Fetches full schema definitions for deferred tools so they can be called.
`
// Matches isDeferredToolsDeltaEnabled in toolSearch.ts (not imported β
// toolSearch.ts imports from this file). When enabled: tools announced
// via system-reminder attachments. When disabled: prepended
// <available-deferred-tools> block (pre-gate behavior).
function getToolLocationHint(): string {
const deltaEnabled =
process.env.USER_TYPE === 'ant' ||
getFeatureValue_CACHED_MAY_BE_STALE('tengu_glacier_2xr', false)
return deltaEnabled
? 'Deferred tools appear by name in <system-reminder> messages.'
: 'Deferred tools appear by name in <available-deferred-tools> messages.'
}
const PROMPT_TAIL = ` Until fetched, only the name is known β there is no parameter schema, so the tool cannot be invoked. This tool takes a query, matches it against the deferred tool list, and returns the matched tools' complete JSONSchema definitions inside a <functions> block. Once a tool's schema appears in that result, it is callable exactly like any tool defined at the top of the prompt.
Result format: each matched tool appears as one <function>{"description": "...", "name": "...", "parameters": {...}}</function> line inside the <functions> block β the same encoding as the tool list at the top of this prompt.
Query forms:
- "select:Read,Edit,Grep" β fetch these exact tools by name
- "notebook jupyter" β keyword search, up to max_results best matches
- "+slack send" β require "slack" in the name, rank by remaining terms`
/**
* Check if a tool should be deferred (requires ToolSearch to load).
* A tool is deferred if:
* - It's an MCP tool (always deferred - workflow-specific)
* - It has shouldDefer: true
*
* A tool is NEVER deferred if it has alwaysLoad: true (MCP tools set this via
* _meta['anthropic/alwaysLoad']). This check runs first, before any other rule.
*/
export function isDeferredTool(tool: Tool): boolean {
// Explicit opt-out via _meta['anthropic/alwaysLoad'] β tool appears in the
// initial prompt with full schema. Checked first so MCP tools can opt out.
if (tool.alwaysLoad === true) return false
// MCP tools are always deferred (workflow-specific)
if (tool.isMcp === true) return true
// Never defer ToolSearch itself β the model needs it to load everything else
if (tool.name === TOOL_SEARCH_TOOL_NAME) return false
// Fork-first experiment: Agent must be available turn 1, not behind ToolSearch.
// Lazy require: static import of forkSubagent β coordinatorMode creates a cycle
// through constants/tools.ts at module init.
if (feature('FORK_SUBAGENT') && tool.name === AGENT_TOOL_NAME) {
type ForkMod = typeof import('../AgentTool/forkSubagent.js')
// eslint-disable-next-line @typescript-eslint/no-require-imports
const m = require('../AgentTool/forkSubagent.js') as ForkMod
if (m.isForkSubagentEnabled()) return false
}
// Brief is the primary communication channel whenever the tool is present.
// Its prompt contains the text-visibility contract, which the model must
// see without a ToolSearch round-trip. No runtime gate needed here: this
// tool's isEnabled() IS isBriefEnabled(), so being asked about its deferral
// status implies the gate already passed.
if (
(feature('KAIROS') || feature('KAIROS_BRIEF')) &&
BRIEF_TOOL_NAME &&
tool.name === BRIEF_TOOL_NAME
) {
return false
}
// SendUserFile is a file-delivery communication channel (sibling of Brief).
// Must be immediately available without a ToolSearch round-trip.
if (
feature('KAIROS') &&
SEND_USER_FILE_TOOL_NAME &&
tool.name === SEND_USER_FILE_TOOL_NAME &&
isReplBridgeActive()
) {
return false
}
return tool.shouldDefer === true
}
/**
* Format one deferred-tool line for the <available-deferred-tools> user
* message. Search hints (tool.searchHint) are not rendered β the
* hints A/B (exp_xenhnnmn0smrx4, stopped Mar 21) showed no benefit.
*/
export function formatDeferredToolLine(tool: Tool): string {
return tool.name
}
export function getPrompt(): string {
return PROMPT_HEAD + getToolLocationHint() + PROMPT_TAIL
}