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

Annotations already indicate destructive and read-write behavior, and the description adds meaningful context by specifying owner or admin access through account-level OAuth or a user-scoped API key. It does not contradict the annotations, though it does not describe potential side effects beyond updating the listed fields.

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?

The description is two sentences with no filler. The first sentence anchors the action and fields, and the second provides the essential auth requirement. Information is front-loaded and every word 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?

The schema and output schema cover parameter details and return values, and the description supplies the authorization context. It is slightly incomplete because it does not explicitly note that at least one updatable field should be provided, nor does it point to list_redirects or list_blogs for discovering the required IDs.

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?

All six parameters are fully described in the schema, so the description needs only to summarize the key fields, which it does by naming source, destination, status code, and active state. It adds no new constraints or format details beyond what the schema already provides.

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 clearly specifies a concrete action ('Update') and target resource ('redirect'), and enumerates the four mutable attributes: source, destination, status code, and active state. This differentiates it from create_redirect and delete_redirect purely by the verb and resource scope.

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?

There is no explicit statement of when to use this tool versus create_redirect or delete_redirect. The update verb only implies the tool applies to existing redirects, and the auth prerequisite is useful but does not provide alternative-routing guidance.

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