Heartbeat check-in (free)

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

No annotations are provided, so the description carries the full burden. It discloses the dead-man switch behavior and the 'at least once per intervalSeconds' constraint, which is useful. However, it does not mention idempotency, error handling, or consequences of missing pings, which would be valuable for a heartbeat tool. The description gives some context but is not comprehensive.

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 description is two sentences, front-loaded with a memorable metaphor, and every phrase carries necessary information. No wasted words; it efficiently conveys purpose, parameter logic, and timing requirement.

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?

For a simple heartbeat tool with two optional params and no output schema, the description is complete. It explains the purpose, the parameter semantics, and the required call frequency. No critical information is missing for an agent to invoke the tool correctly.

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 0% and there are only two string parameters. The description adds significant meaning by explaining that pingUrl comes from create_watch and that watchId alternatively refers to ping URLs in local state. It clearly clarifies the source and trade-off between the two parameters, fully compensating for the lack of schema documentation.

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 identifies the tool's purpose with a specific metaphor: 'Keep a dead-man switch alive.' It distinguishes itself from sibling tools like create_watch (which creates watches) and watch_status (which checks status) by indicating this is the periodic check-in mechanism that must be called regularly.

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?

The description provides clear usage context: pass pingUrl from create_watch or watchId, and call at least once per intervalSeconds. It names the source parameter and the frequency, giving clear when-to-use guidance. However, it does not explicitly mention alternatives or exclusions, such as using watch_status for status checks.

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