cocos_list_tools

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden. It discloses key behavioral traits: it's a read-only operation (implied by 'list'), returns structured data with count and tools array, explains the 'summary' field derivation, describes filtering behavior, and states that empty filters return all tools. It doesn't mention rate limits, authentication needs, or pagination, but covers the core behavior well for a listing tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is appropriately sized and well-structured. It starts with the core purpose, addresses the specific problem scenario, describes the return format, explains parameters with examples, and ends with usage guidance. While somewhat detailed, every sentence adds value. It could be slightly more concise but remains efficient.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (2 parameters, no output schema, no annotations), the description is complete. It explains the tool's purpose, when to use it, behavioral details, parameter semantics, and return format. The lack of output schema is compensated by describing the return structure. For a listing tool with filtering, this provides sufficient context for an agent to use it correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema description coverage is 0%, so the description must fully compensate. It provides detailed semantics for both parameters: 'name_contains' is explained as 'case-insensitive substring on the tool name' with concrete examples ('joint', 'scaffold'), and 'category' is described as 'coarse bucket inferred from the name prefix' with a complete list of possible values. The description also clarifies that both are optional and that empty filters return every tool.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'List the tools actually registered on this MCP server.' It specifies the exact resource (tools) and verb (list), and distinguishes itself from siblings by addressing stale-catalog scenarios and providing ground truth about server capabilities.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit guidance on when to use this tool: 'Addresses stale-catalog scenarios where a subagent's MCP session can't reliably see tools registered after the session started' and 'Use this whenever you need to double-check whether a capability is already baked in before implementing it manually.' It also explains the alternative (asking the server directly vs. relying on session state).

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.