x_timeline_user

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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds useful behavioral context: newest-first ordering, optional filters, a compact/sanitized page, and a third-party content warning. It does not disclose rate-limit or auth specifics, but those are less critical given the annotations.

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?

Two sentences with no filler: the first states the core purpose and options, the second adds the important safety caveat. Front-loaded action and resource make it easy to scan.

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 an 8-parameter read-only tool with full schema coverage and an output schema, the description covers purpose, ordering, filtering options, output nature, and a safety warning. Nothing needed for correct selection or invocation is missing.

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 the input schema already documents all eight parameters. The description reinforces the filtering and time-bound options but does not add meaning beyond the schema; baseline 3 applies.

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?

States a specific verb ('Read'), the resource ('an X (Twitter) user's own posts'), and ordering ('newest first') plus filtering options. This separates it from sibling x_timeline_home and x_timeline_mentions, which cover different timelines.

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 clearly implies the tool is for reading a specific user's authored posts and mentions optional filters, but it does not explicitly say when to prefer it over alternatives like x_timeline_home or x_timeline_mentions, or when not to use it. Usage context is inferred rather than stated.

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