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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so safety is covered. The description adds two genuinely new behavioral facts: liker lists are frequently author-restricted (empty results are normal, not an error) and output is paginated. Auth details and rate limits remain unstated.

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?

Three tight sentences: purpose, the empty-results caveat, then pagination. No repetition, no filler, and the most decision-relevant fact (author-only visibility) is surfaced early.

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, fully-schema-documented tool with rich annotations, the description covers the two things an agent could not infer: the author-restriction caveat and pagination. It could say slightly more about the shape of a returned liker (user objects) given there is no output schema, but that is a minor gap.

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% and each of the five parameters (count, cursor, format, max_chars, tweetId) is documented in-schema with defaults and constraints. The description adds only the word 'Paginated', which lightly reinforces the cursor parameter but nothing beyond the schema.

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 states a specific verb and resource ('Get the users who liked a tweet'), which unambiguously separates it from its closest siblings get_tweet_retweets and get_tweet_quotes. An agent can select it without opening the schema.

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 caveat that X only exposes likers to the tweet's author tells the agent to expect empty results in many cases, which is real selection context. However, it never explicitly says when to prefer this over alternatives or what to do instead when it returns nothing.

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