Trait info

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

The description uses 'Fetch' which aligns with annotations readOnlyHint and idempotentHint. It adds that the tool returns PGS IDs, providing useful behavioral context beyond the annotations. No contradictions.

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, efficient sentence that conveys the purpose, method, and key output. Every word is necessary and front-loaded.

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?

For a simple read-only tool with a single parameter and an output schema, the description adequately explains the core functionality and mentions the key return element (PGS IDs). It does not address error cases like missing EFO IDs, but the openWorldHint and presence of an output schema reduce the need for further detail.

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 sole parameter efo_id has no schema description (0% coverage), but the tool description compensates by specifying the format ('EFO_...') and providing an example, making the parameter's meaning and expected value clear.

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 verb 'Fetch', the resource 'trait by EFO ID', and the associated data 'with its associated PGS IDs'. It includes an example EFO ID, which distinguishes it from sibling tools like search_traits that search without a specific ID.

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 no guidance on when to use this tool versus alternatives such as search_traits or score_info. It simply states the function without any context about when to prefer it or when not to use it.

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