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

Annotations already declare idempotentHint=true, destructiveHint=false, and readOnlyHint=false; the description adds the meaningful stateful behavior — push webhook vs pull token modes, webhook auto-detection (generic/Slack/Discord), and that it returns a token to manage/poll. It doesn't cover subscription lifetime or cleanup, but adds real context beyond the annotations.

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?

Front-loaded with the core action and scoping, then the push/pull distinction, then the trigger. Dense but every sentence carries information; slightly long with some redundancy between 'Subscribe' and 'Call this to be told...'.

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?

With no output schema, the description usefully explains that a token is returned for managing/polling the subscription, and covers both delivery modes. It leaves subscription lifecycle details (expiry, cleanup) unstated, but the essentials for correct invocation are present.

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 coverage is 100%, so the baseline is 3, but the description adds genuine meaning: it explains the webhook parameter's auto-detection behavior and the semantic split (webhook present = push, omitted = pull token), which the schema only hints at. minSeverity and allCritical are left to the schema.

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 (subscribe) and resource (reliability alerts for tools, or all critical outages), clearly differentiating it from siblings like unwatch and get_notifications. An agent can tell immediately this is the subscription-creation tool.

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 a clear trigger ('Call this to be told the moment a tool you depend on breaks or recovers') and names the pull alternative (get_notifications) plus the condition that selects it (omit webhook). It does not explicitly say when NOT to use it versus unwatch, so it falls short of a full 5.

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