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

The description discloses real side effects beyond the annotations: subscriber emails and Slack posts are triggered, matching console behavior, which is critical given destructiveHint=true. It also explains the opened_at/resolved_at backfill semantics that the annotations cannot express. It does not state that each call creates a separate incident (no idempotency implication) or what the response contains.

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?

Purpose, side effects, the gating constraint, then parameter semantics — well front-loaded and dense with no filler sentences. The transition into parameter notes is slightly abrupt but every sentence carries 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 an 8-parameter destructive tool with no output schema and zero schema descriptions, the description covers purpose, side effects, invocation gating, and the critical enum/format semantics. The remaining gap is the unexplained required 'slug' and no indication of what is returned, but overall an agent can call this 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 description coverage is 0%, so the description carries the burden, and it does supply the missing enum values for status and impact plus the meaning of component_ids and the opened_at/resolved_at pairing. However, 'slug' — a required parameter — is never explained (which status page it refers to), and title/body are left entirely implicit.

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 opening sentence 'Open an incident' gives a specific verb and resource, and the side-effect sentence clarifies it is the real, publishing version rather than a draft. It does not explicitly name sibling tools like update_incident or post_incident_update, so differentiation is inferable rather than stated.

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?

'Run only when the user asked to publish this incident in this conversation' is an explicit gating condition that rules out proactive use, which is unusually strong guidance for a mutating tool. It stops short of naming alternatives for related workflows (e.g. use update_incident to amend an open one), so it is clear context without full routing.

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