Fetch Actor Timeline

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

The annotation 'readOnlyHint: true' already indicates a read-only nature. The description adds 'with pagination support', which is marginally useful but already evident from the parameters. No additional behavioral details (e.g., rate limits, caching) are disclosed, so the description adds little beyond the annotation.

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, front-loaded sentence that efficiently conveys the core action and support for pagination. No unnecessary words, earning a top score.

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 6 parameters defined in the schema, no output schema, and the annotation providing safety context, the description is largely complete. However, it could elaborate on the return format (list of posts) or pagination behavior, leaving minor room for improvement.

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?

Schema description coverage is 100%, with each parameter having a clear description. The tool description only mentions 'pagination support', which adds no new meaning beyond the schema. Thus, it meets the baseline of 3.

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 'Fetch posts from any actor's timeline' with the title confirming 'Fetch Actor Timeline'. This differentiates it from sibling tools like 'get-home-timeline' (own timeline) and 'get-public-timeline', though it does not explicitly contrast them.

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 implies this tool is for fetching any actor's timeline, but provides no explicit guidance on when to use it versus alternatives such as 'get-home-timeline' for one's own feed. The context of sibling tools offers implicit differentiation, but direct instructions are missing.

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