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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds materially beyond that: 2 credits per call, failed calls cost 0, one call per page so limit=100 means multiple calls, and error handling via error.fix plus telling the user billing.display. That is genuine behavioral context an agent cannot get from 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?

The platform matrix is useful but dominates the description and is written in compressed fragments ('Each line: what to pass (a|b: either one), then platforms at 2 credits a call unless numbered') that require parsing effort. The core action and the cost/pagination facts are buried rather than 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?

For a 10-parameter, no-output-schema tool it covers identifiers, cost, pagination, and error recovery, which is more than most. It does not describe what a result contains (no output schema to lean on) and references a limit parameter that the schema does not define, leaving the agent's contract incomplete.

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?

With 70% schema coverage, the description adds real meaning: which of id/username/url to supply per platform, and 'type=answer|pin: zhihu'. Against that, it instructs 'Pass limit=100' but no limit property exists in the schema, and 'More parameters: capabilities' ambiguously references what is actually a sibling tool. Those are likely to produce invalid calls.

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 opening sentence gives a specific verb and resource: 'List what one account has published,' which tells an agent this is a per-account post listing rather than a search. However, it never contrasts with siblings like user_profile, detail, or search, so the boundary is inferred rather than stated.

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 bulk of the text is an identifier matrix (id vs id|url vs username per platform), which is real invocation guidance. There is no when-to-use / when-not-to-use framing and no pointer to an alternative sibling when this tool is wrong.

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