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

With no annotations, the description must explain behavior fully. It states the core trigger (stop checking in -> fire webhook) but omits crucial details: is this a one-time firing or recurring? Does the switch persist? What is the role of interval_seconds and days? Are there side effects like resource cleanup? This is insufficient for a mutation tool with lifecycle.

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 a single, memorable sentence that immediately conveys the tool's purpose. However, it earns this score by being too terse; it sacrifices useful behavioral and parameter context for brevity.

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 tool with 4 parameters and no output schema, the description is incomplete. It doesn't mention the companion checkin_deadman tool, the firing behavior, or explain the 'days' parameter. A new user would need to explore further to use this 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?

The description provides no parameter-level context. The schema covers 3 of 4 parameters, but 'days' has an empty description, and the description doesn't clarify how days relates to interval_seconds or the dead-man switch logic. Users are left to guess the semantics of days.

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 explains the dead-man switch concept: it fires your alert webhook if you stop checking in. This distinguishes it from sibling tools like create_watch or create_schedule, which have different trigger mechanisms. The behavior is specific and actionable.

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?

No guidance on when to use this tool versus alternatives like create_watch or create_schedule. The description doesn't mention that checkin_deadman is the companion tool for periodic check-ins, nor does it specify any preconditions or post-conditions.

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