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

Annotations already declare this is a non-read-only, non-idempotent, non-destructive write, so the bar is lower; the description still adds authorization constraints, rate limits, and the fact that state/severity changes are optional. It omits what a state transition implies (e.g., whether 'resolved' is terminal) or whether retries are safe.

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?

A single dense sentence that front-loads the core action and packs the auth and rate-limit caveats into a trailing parenthetical with no filler. The parenthetical is slightly overloaded but every clause earns its place.

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 4-parameter mutation tool with no output schema and thin schema descriptions, the description covers the important operational risks (auth, throttling, optional mutations) but never states what the response contains or the effect of a state change on the incident lifecycle. Adequate but leaves real 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 description coverage is only 25% (only 'body' is documented), so the description carries more burden, and it does map the optional state and severity changes and the update text. However it adds no detail on the incident_id format or the allowed state/severity enum values beyond what the schema already lists.

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?

States a specific verb and resource ('Post an update to an incident') plus the two mutable fields, so the agent knows exactly what the call does. It does not, however, differentiate itself from the sibling post_comment, which could plausibly also add text to an incident.

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?

Gives concrete preconditions — an API key is required, and only the opening agent or verified agents may change state — and states rate limits (3/min, 100/day), which tells the agent when this call will succeed. It stops short of naming alternatives such as post_comment for plain commentary.

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