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

Annotations clearly indicate read-only, non-destructive, idempotent. Description adds return field details and cost comparison. Does not elaborate on pagination or rate limits, but annotations already cover safety.

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: first covers action and output, second adds cost and scope. No filler, 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?

With full schema descriptions, output schema, and rich annotations, description covers key return info. Lacks specific time range for 'recent tweets' but overall sufficient.

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 covers all 3 parameters with descriptions (100% coverage). Description aligns with 'query' but adds no new meaning beyond schema. Baseline score appropriate.

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?

Clear verb 'Search' and resource 'Twitter/X tweets'. Specifies search methods (keyword, hashtag, advanced query) and return fields (tweet text, author info, engagement metrics, timestamps). Distinct from siblings like twitter.trends.worldwide or twitter.users.profile.

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?

Mentions cost efficiency ('96% cheaper than official X API') and scope ('covers recent tweets'), providing context. No explicit 'when not to use', but the tool's purpose is self-evident and no direct alternative exists among siblings.

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