{"rule_id":"AB-020","category":"machine_readable","icon":"🛠️","title":"MCP Tools List","short_description":"Your MCP server responds to tool listing requests.","user_value":"Agents need to see what tools your MCP server offers before they can use any of them.","wrong_example":"MCP server doesn't respond to tool listing. Agents don't know what's available.","right_example":"MCP server lists all available tools with descriptions.","effort_hint":"moderate","estimated_cost":"$10-50","severity":"high","pillar":"discovery","version":"1.0.0","counted_in_score":true,"check":{"type":"json_rpc","sources":["mcp"],"target":"/mcp"},"fix":{"eligible":false,"type":"none","note":"Implement MCP tools/list JSON-RPC method"},"checklist_anchor":"#AB-020","checklist_url":"/agent-readiness-checklist#AB-020","html_url":"/rules/AB-020","json_url":"/rules/AB-020.json","related_rules":[{"rule_id":"AB-010","title":"Machine-Readable Pricing","category":"machine_readable"},{"rule_id":"AB-011","title":"Rate Limits Declared","category":"machine_readable"},{"rule_id":"AB-012","title":"Structured Error Responses","category":"machine_readable"},{"rule_id":"AB-021","title":"MCP Tool Calls","category":"machine_readable"},{"rule_id":"AB-022","title":"MCP Streaming Support","category":"machine_readable"},{"rule_id":"AB-109","title":"Agent Card version 1.0.0+","category":"machine_readable"},{"rule_id":"AB-163","title":"Skill.json (JSON-LD) availability","category":"machine_readable"},{"rule_id":"AB-164","title":"Error catalog endpoint","category":"machine_readable"}]}