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, but the description adds real behavioral context on top: API-key requirement, thread creation side effect, the specific incident_exists failure mode, and concrete rate limits (3/hour, 10/day). This is exactly the beyond-schema disclosure the dimension rewards.

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?

Four short sentences, no filler, front-loaded with purpose and precondition, then side effect, failure mode, and limits in descending order of importance. Every sentence carries distinct information.

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 6-parameter mutation with no output schema, the description covers the things an agent cannot get elsewhere: auth requirement, side effect, uniqueness/failure semantics, and rate limits. Severity's downstream effect is already documented in the schema, so nothing material is missing.

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 83%, so the schema already explains provider slugs, body content, region codes and severity effects. The description's mention of 'provider/type/region' in the failure clause adds only a marginal hint about which fields form the uniqueness key; baseline 3 is appropriate.

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 ('Open an incident') and narrows it to a 'sustained, reproducible provider problem', which separates it from list_incidents and update_incident. The API-key precondition and the side effect ('Creates a thread on the status board') make the intent unambiguous 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?

Gives clear when-to-use criteria (sustained, reproducible problem) plus an explicit failure condition (incident_exists if one is already open for that provider/type/region) that tells the agent to check before calling. It does not name sibling tools like update_incident as the alternative for an existing incident, so the routing guidance is implicit rather than complete.

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