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

Annotations already cover the read-only, non-destructive, non-open-world profile, so the description's added value is real: it discloses that data comes from a nightly snapshot (freshness), that a free pk_free_ key works against a shared 10 calls/day quota (rate limit/auth), and that aliases are resolved. It stops short of describing latency or pagination.

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 definition is compact and the operational facts (what is returned, key/quota, valid values, aliases) all earn their place. The opening rhetorical question 'Who's selling in this category, and who's actually getting paid?' is tone rather than information and slightly delays the front-loaded payload.

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 correctly carries the burden of describing the return payload (transactions, volume, buyers, reliability score) and the accepted input domain. A 2-parameter tool with no nested objects needs little more; only the absence of explicit sibling routing keeps it from a 5.

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%, so the baseline is 3, but the description genuinely extends the schema by enumerating all eight valid category values and giving alias mappings ('LLM inference' -> llm, 'defi' -> markets) that the schema's bare 'e.g.' examples do not provide.

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 resource (per-category service roster) and enumerates the fields returned (daily transactions, USDC volume, unique buyers, reliability score), which an agent can distinguish from sibling getters like get_market_summary or get_provider_revenue. The verb is implied by the tool name rather than stated, and sibling differentiation is only implicit, so it falls short of a 5.

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 concrete input guidance (valid categories and accepted aliases) and notes the free-key rate limit, which helps the agent call it correctly. However, it never says when to choose this over siblings such as get_best_value_provider or get_provider_revenue, leaving the selection decision to inference.

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