Agent Tool

Create or modify an agent tool: $ARGUMENTS

Before Starting

1. Search OpenAI docs for latest tool patterns:
   • Use mcp__openai-docs__search_openai_docs with query "Agents SDK tool definition" for current tool() helper signature
   • Use mcp__openai-docs__search_openai_docs with query "Agents SDK function tools parameters" for parameter schema patterns
2. Read existing tool implementations:
   • /Users/joshuashepherd/Desktop/Dev/repos/ai-lab-agent/src/agents/ai-lab/tools/base.ts — search_books, file_search tools with caching + metrics
   • /Users/joshuashepherd/Desktop/Dev/repos/movemental-dashboard/src/agents/seo-expert/tools.ts — 9-tool suite (analyze, research, score, optimize, generate)
   • /Users/joshuashepherd/Desktop/Dev/repos/ai-lab-agent/src/agents/ai-lab/tools/utils.ts — executeToolWithMetrics(), timeout constants
3. Read the shared tool infrastructure:
   • /Users/joshuashepherd/Desktop/Dev/repos/ai-lab-agent/src/services/toolCacheService.ts — param-based LRU caching with TTL

Tool Template

import { tool } from '@openai/agents';
import { z } from 'zod';
import type { RunContext } from '@openai/agents';

export const myTool = tool({
  name: 'my_tool',
  description: 'Clear, specific description of what this tool does and when the agent should use it.',
  parameters: z.object({
    query: z.string().describe('What to search for'),
    maxResults: z.number().optional().default(5).describe('Maximum results to return'),
  }),
  strict: true,
  execute: async (params, context?: RunContext<MyContext>) => {
    // 1. Check cache (if applicable)
    const cacheKey = `my_tool:${params.query}`;
    const cached = await toolCacheService.get(cacheKey);
    if (cached) return cached;

    // 2. Execute with metrics and timeout
    const { result } = await executeToolWithMetrics('my_tool', async () => {
      // Tool implementation here
      return { data: 'result' };
    }, TOOL_TIMEOUTS.MEDIUM);

    // 3. Cache result
    toolCacheService.set(cacheKey, result).catch(() => {});

    return result;
  },
});

Patterns by Tool Type

Search / Retrieval Tools

• Return structured results with title, snippet, url/slug, relevance score
• Always include a maxResults parameter with sensible default
• Gracefully degrade when external service is unavailable (return empty array, not error)
• Add citation metadata when results reference source material

Analysis / Computation Tools

• Accept content as string input
• Return structured analysis object (scores, categories, suggestions)
• Include confidence scores where applicable
• Keep descriptions prescriptive so the agent knows when to invoke

API Integration Tools

• Validate API keys exist before calling
• Set appropriate timeouts (TOOL_TIMEOUTS: SHORT=5s, MEDIUM=15s, LONG=30s)
• Return user-friendly error messages, not raw API errors
• Never expose API keys in tool results

Database Query Tools

• Use the service layer (never raw SQL in tools)
• Scope by organizationId from context for multi-tenant safety
• Return only fields the agent needs, not entire rows

Registration

After creating the tool, register it with the target agent:

Static registration (simple agents):

// In the agent's index.ts
import { myTool } from './tools';
export const myAgent = new Agent({
  tools: [myTool, existingTool1],
});

Dynamic registration (function-based agents):

// In the agent's tools/index.ts
export function getToolsForConfiguration(context: RunContext<MyContext>): Tool[] {
  const tools = [...getBaseTools()];
  if (context.context.someCondition) {
    tools.push(myTool);
  }
  return tools;
}

Rules

• Tool names must be snake_case
• Descriptions should tell the agent WHEN to use the tool, not just what it does
• Parameters must use Zod schemas with .describe() on every field
• Always handle errors gracefully — return error objects, never throw
• Cache results when the tool calls external services
• Wrap execution in executeToolWithMetrics() for observability
• Tool results are sent to the LLM — keep payloads concise (truncate large results)
• Check OpenAI docs MCP for any SDK changes to the tool() helper before generating code