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

Beyond the readOnlyHint annotation, the description adds meaningful behavioral guarantees: it never returns raw credentials and only returns non-sensitive metadata such as slugs, aliases, categories, and resolver guidance. It also communicates the 'wallet-resolved' nature of the lookup, giving an agent a clear safety and output model.

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 three focused sentences: what the tool does and its safety guarantee, when to use it, and what it returns. It is front-loaded with the most important distinction and contains no filler or redundant restatement of the title or schema.

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?

With only one optional, fully documented parameter, a readOnlyHint annotation, and an output schema, the description covers all necessary context. It explains the tool's purpose, triggering scenarios, output contents, and safety boundary, so an agent has enough information to invoke 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 input schema already provides full descriptions of the single optional query parameter, including examples and natural-language support, so schema description coverage is 100%. The tool description adds use-case context but does not add additional parameter-level semantics beyond what the schema already states.

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 uses a specific verb and resource: it 'discovers wallet-resolved credential service names and accepted aliases' while explicitly stating it does not expose secret values. It also names concrete use cases and clarifies that it returns only metadata like service slugs, aliases, categories, and resolver guidance, which clearly distinguishes it from a credential-fetching tool.

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 gives explicit contexts for use: when an agent is unsure whether a key exists, encounters a key-not-found error, or needs the canonical getAgentKey(service) name. It does not describe when not to use the tool or name alternatives, but the guidance is specific enough for an agent to select this tool correctly.

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