x402 watch — renew 30 days (paid)

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

No annotations provided, so description carries full burden. Discloses that secret stays same and payment model, but omits behavior on invalid watch_id or expired watch, and does not mention idempotency or side effects.

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?

Two sentences with no superfluous words. Information is front-loaded and efficiently conveys core functionality, payment, and secret persistence.

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?

No output schema, so description should explain return format. It vaguely mentions 'returns the price quote,' but does not specify structure or cover error cases like missing watch or expired watch. Lacks completeness for a mutation tool.

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% and parameter description in schema is adequate ('Watch id returned by x402_watch_create'). The tool description adds no extra meaning about the parameter itself, only behavioral context.

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?

Clearly states the tool extends an active watch by 30 days, distinguishing it from sibling tools like x402_watch_create (creates) and x402_watch_events (lists events).

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?

Specifies timing ('before it expires') and payment behavior (auto-pay or price quote). However, it does not explicitly state when not to use it (e.g., if watch expired) or mention alternatives like creating a new watch.

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