Get User List Memberships

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

Goes well past the annotations by disclosing auth needs (TweetAPI API key), request/cost profile (one request, ~1 unit, cost estimate in each result), and pagination mechanics (one page per call, resume via completeness.nextCursor). It also notes Private Lists are included with a mode field, which is real behavioral context. The only slight redundancy is restating 'Read-only', which readOnlyHint already covers.

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?

Front-loaded with purpose, then usage split, then cost/auth, then pagination — a sensible ordering with almost no wasted wording. It is a single dense paragraph, though, so a few clauses (the 'Read-only' restatement) could be trimmed.

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 a read-only, single-page list endpoint with an output schema, the description covers everything an agent needs: how to identify the right view, how to resume pagination, what a call costs, and what auth is required. Nothing essential 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 coverage is 100%, so cursor, userId, and responseFormat are already documented in the schema. The description reinforces the cursor contract by tying it to completeness.nextCursor, but adds no syntax or format detail the schema lacks, so the 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 and resource plus scope: 'Fetch one page of the Lists a user has been added to as a member', and anchors it to the concrete UI surface ('the Member of view on x.com'). It immediately distinguishes itself from the nearest sibling by naming tweetapi_user_lists for the opposite view.

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?

Gives explicit routing: use this for Lists the user was added to, use tweetapi_user_lists for the user's own Lists tab. It also pre-empts a common mistake by telling the agent that owners can be any account and must be checked per List.

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