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

Annotations already signal read-only, idempotent, non-destructive behavior, so the description adds meaningful behavioral detail beyond them: page size (up to 20), cursor-based pagination, ordering matching the X profile, optional inclusion of replies/parent tweets, and the absence of time-range filtering. This gives the agent a strong model of runtime behavior.

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 front-loaded with the core purpose twice in the first sentence, then efficiently covers pagination, optional parameters, usage context, and alternatives without redundancy. Every sentence earns its place, and the structure guides the agent from main behavior to edge cases.

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?

Given the output schema exists and annotations cover safety, the description provides everything needed to select and invoke the tool correctly: parameter format, ordering, pagination, filtering limitations, and sibling routing. No critical operational context 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?

The schema already documents all 4 parameters with 100% coverage, establishing a baseline of 3. The description adds value by emphasizing that userId must be numeric, explaining cursor semantics ('pass the returned cursor for more'), and mapping the include flags to behavior. It doesn't deeply redefine each parameter, but the extra context justifies a score above baseline.

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 a specific verb and resource: retrieve a user's own tweets by numeric userId, with explicit ordering (newest first) and scope. It also distinguishes itself from siblings by naming alternatives like get_twitter_user_mentions and get_twitter_user_last_tweets, so an agent can tell them apart immediately.

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?

It explicitly states when to use this tool ('Use this to read what an account publishes over time') and when not to, noting that time-range filtering is NOT supported and pointing to get_twitter_user_mentions and get_twitter_tweet_advanced_search for date-window queries. It also covers the handle-only case by referencing get_twitter_user_last_tweets, leaving no ambiguity about alternatives.

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