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

The description clearly describes a mutating operation: it schedules an alarm, causes future webhook POSTs, and charges the caller. The annotations declare readOnlyHint=true, which directly contradicts the described behavior of creating state and incurring cost. This is a serious annotation contradiction.

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 front-loaded with the core action and packs timing, retry, signing, cost, and management endpoints into a compact paragraph. It is dense but not wasteful. Slight readability cost from being a single long paragraph rather than broken into sentences or bullets.

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 complex, stateful tool with no output schema, the description covers timing bounds, retry behavior, HMAC signing, pricing, and how to check or cancel an existing alarm. It does not explicitly state what set_agent_alarm returns (for example, an alarm id), which is a gap given there is no output schema. The annotation contradiction also reduces confidence in the overall completeness.

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%, so the input schema already documents every parameter. The description adds some useful context about signing and retry timing, but it also mentions a signing_secret that is not an input parameter, which may confuse parameter semantics. Baseline 3 is appropriate when the schema does most of the work.

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 states a specific verb and resource: scheduling a signed webhook to wake an AI agent later. It distinguishes the tool from all listed siblings, none of which concern delayed webhook alarms. An agent can identify the tool's purpose without opening the schema.

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 gives context for use (schedule a webhook for later, check status for free, cancel for free, charged only when accepted), but it never states explicit when-to-use or when-not-to-use conditions versus alternatives. There are no sibling tools with overlapping functionality to route against, so the guidance is implied rather than explicit.

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