find_contact_by_email

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

No annotations are present, so the description carries the full burden of behavioral disclosure. It only says 'look up', which suggests a read operation but does not mention auth requirements, not-found behavior, or non-destructive guarantees.

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 a single sentence with no unnecessary words. It is appropriately front-loaded and concise.

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?

The tool is simple and an output schema is present, so return values likely do not need description. However, the omission of api_token semantics and the lack of any usage context leave moderate gaps for an agent deciding when and how to invoke the tool.

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 description adds meaning to the 'email' parameter by mentioning 'email address', but the 'api_token' parameter is completely unaddressed. With 0% schema description coverage, the description should compensate for all parameters but only covers one.

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 ('look up') and identifies the resource ('contact') and lookup key ('email address'). It clearly distinguishes the tool from siblings like upsert_contact, which is for creating or updating contacts.

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 intended usage is implied by the name and description, but there is no explicit guidance on when to use this tool versus alternatives. No comparisons to search_conversations or other lookup tools are provided.

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