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

With no annotations, the description carries the full burden and does so: it discloses the authorization requirement, the self-approval prohibition, that approval notifies the applicant, that the transaction re-validates permission/consent/join-batch server-side, and that no contact details are returned (privacy guarantee). This is exactly the mutation-risk context an agent needs.

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 permission bracket, then actions, constraints, and the preview protocol — no filler sentences. The telegraphic, heavily punctuated style packs a lot in but is denser than ideal for quick scanning.

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 tool with no annotations and no output schema, the description covers permission, safety rules, the preview/confirm protocol, and privacy. What it omits is the shape of the preview response (presumably the previewHash) and post-revoke behavior, minor gaps against an otherwise thorough definition.

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 0%, so the description must compensate. It explains the three action values, the preview default of true, and the previewHash confirmation handshake (same params + hash, preview=false), plus that note is reviewed. However, activityRef and requestId receive no explanation beyond an implicit 'this session' / 'the request', leaving two of six parameters opaque.

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 states a specific verb set (approve/reject/revoke) applied to a specific resource (activity cloud contact authorization requests) and describes the effect of approval: opening designated member contact rights to the applicant plus notification. This distinguishes it from the sibling list_activity_cloud_contact_requests (which only reads requests) without needing 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?

Explicit preconditions and exclusions are given: contact-management permission is required and self-approval is forbidden. The two-step workflow is spelled out — default is preview, and confirmation requires the same parameters plus previewHash with preview=false, with a re-confirm rule if anything changed.

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