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

Annotations declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, and the description adds genuinely new behavioral context: the required server-to-server X-Agent-Key auth header, explicit confirmation, that the HMAC key and webhook are never returned, and the caveat that a stored watch does not prove alert delivery. These are auth, secret-handling, and expectation-setting details the annotations cannot carry.

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 action and the auth requirement, and every sentence carries information (requirements, secret retention, read-only fallback, delivery caveat). Slightly dense, but no wasted filler.

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 mutation tool with no output schema, it covers auth, confirmation, secret handling, the read-only fallback, and a meaningful limitation. It leaves only minor gaps, such as the return shape on success and the meaning of the idempotentHint.

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 83%, so the schema already documents most parameters. The description adds value beyond that by stating the one-of constraint between country and domain, that the webhook must be public HTTPS, that the HMAC key is caller-generated, and that confirmation is required — though it omits min_severity.

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 opens with a specific verb+resource: "Create one DID-owned Atlas incident watch." It names the resource ('Atlas incident watch') precisely enough to distinguish it from watch_list and watch_delete, and adds scope ('DID-owned') that no sibling shares.

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?

It clearly states the condition that changes behavior: a caller with the X-Agent-Key header creates a watch, while "a bare scope without the header remains a read-only setup check." That is strong when-to-use context, but it does not explicitly route to the watch_list/watch_delete siblings or name exclusions.

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