Read a list's timeline

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the description only adds the scope that it returns statuses from accounts on the user's lists and where to obtain list IDs. This is useful context but not rich behavioral detail beyond what annotations and schema already convey.

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 two sentences, front-loading the core purpose and immediately pointing to get_lists for the required list_id. No unnecessary words; each sentence earns its place.

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 read-only timeline tool with full schema descriptions and annotations, the description is sufficient: it explains what it returns, where to find the required list_id, and the schema covers all parameters and pagination details. It lacks explicit authentication notes but that is implicit across the toolset.

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%, so all five parameters are documented in the schema. The tool description does not add any additional parameter semantics beyond the schema, matching the baseline for full schema coverage.

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 resource (a list's timeline) and the action (retrieve statuses), and explicitly distinguishes it from other timeline tools by referencing 'one of your lists' and pointing to get_lists for list IDs. This separates it from siblings like get_home_timeline or get_local_timeline.

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 usage context by noting it's for lists you own and provides a prerequisite (find list IDs with get_lists), but it does not explicitly state when to use this tool versus alternatives like get_home_timeline or get_hashtag_timeline. The guidance is implied rather than explicit.

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