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

Annotations only declare safety flags, and the description goes well beyond them: exact cost (1 credit per successful call), the fact that repeat comparisons are still charged, and that failures are free and name the offending account. For a metered operation, those details are exactly what an agent needs to avoid wasting credits.

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 purpose is front-loaded in one sentence, followed by the cost and failure model. The second sentence is a bit run-on and repeating 'even for accounts compared before' could be tighter, but every clause carries real information.

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 no output schema, the description compensates by naming the returned metrics, and it fully covers pricing and the failure mode. Missing pieces are minor: the exact response shape and whether all accounts must be on the same platform.

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 both parameters, the enum platform, and the 2-to-10 account bounds are already documented in the schema. The description only implies that multiple creators are compared, adding no syntax or format detail beyond the structured fields. 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?

The description names a specific computation (audience overlap between several creators) and even states the two outputs, unique reach and per-creator overlap share, so the agent knows exactly what it gets back. It does not distinguish itself from the sibling compare_influencers, which is the one ambiguity left.

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 gives actionable calling guidance: just call it directly, because a nonexistent account or one without follower data fails without charging. That rules out the wasteful pre-check pattern. It does not, however, say when to prefer compare_influencers or get_influencer_report instead.

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