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

Goes well beyond the annotations by disclosing cost (USD 0.01/Actor), the 1-20 cap, that it is public API reads only, that results are heuristics rather than Apify's own decision, timing expectations (2-10s, up to a minute for 20), and a prompt-injection warning about untrusted returned text. These are meaningful operational caveats not derivable from the readOnly/idempotent 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?

Front-loaded with the purpose and alternative routing, which is good, but the text is redundant: pricing is stated twice ("USD 0.01 per Actor, up to 20" and again "Price: USD 0.01 per Actor (1-20 Actors per call)"), and the untrusted-data warning appears twice. Several sentences could be merged without loss.

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 an output schema present, return-value explanation is unnecessary, and the description covers everything else an agent needs: scope, cost, limits, timing, interpretation caveats, and safety warnings. Complete for this tool's complexity.

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 the single 'actors' param is fully documented in the schema with its accepted id/username~name/URL formats. The description reiterates the 20-item cap and cost but adds no format or syntax detail beyond the schema, 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 (check) and resource (Apify Actors against Store publishing rules), and enumerates the exact checks performed (outside payment links, README/pricing disagreements, near-duplicate listings). It explicitly distinguishes itself from sibling alternatives, so an agent can route correctly without opening schemas.

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?

Explicitly names the alternatives and the conditions that select them: preflight_mcp_listing for an MCP server repo vs an awesome list, and check_agent_readiness for a site's AI-agent readiness. This is textbook when-to-use/when-to-use-something-else guidance.

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