pay

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

Annotations already indicate openWorldHint=true and readOnlyHint=false. Description adds value by disclosing side effects ('may settle USDC via x402') and return types (payment_required with pay_to/amount). No contradictions.

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?

Well-structured with a one-line summary, usage guidelines, args, and return info. Every sentence adds value, though slightly verbose in the args section. Good front-loading.

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 tool complexity (3 params, 1 required, output schema exists), description covers purpose, usage guidance, side effects, return types, and error conditions. No gaps.

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 baseline is 3. Description repeats parameter descriptions from schema but adds minimal extra context (e.g., examples for slug). Does not significantly enhance beyond schema.

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 clearly states 'Call any Vibes-Coded outcome by slug' with optional payment, and distinguishes from dedicated tools like vc_web_search. It specifies the action, resource, and scope precisely.

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 describes when to use (catalog outcomes without dedicated tool, retry after payment_required) and when not (instead of health). Also advises preferring prepaid keys, providing clear decision guidance.

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