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

Beyond the annotations (readOnlyHint false, destructiveHint true, etc.), the description discloses critical behaviors: the grant_url token is shown once and not recoverable, list never returns a token, revoke is idempotent, pins never widen access, and the write-only grant read-back caveat. This is far richer than the structured hints alone.

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 dense but every sentence earns its place, covering definition, actions, modes, pin behavior, and a security-relevant caveat. It is well-structured, front-loaded with the core concept, and contains no filler or redundant repetition.

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 10-parameter, multi-action tool with no output schema, the description is unusually thorough: it describes mint/list/revoke, token handling, once/multi modes, pin narrowing, and a subtle security consequence. It stops short of fully describing return shapes for list/revoke and error behavior, but the schema and annotations fill some gaps.

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?

The input schema already covers 100% of parameters with descriptions, so the baseline is 3; the description adds meaningful context on top—mode explanations, pin narrowing semantics, and the max_uses cap within expiry. It enriches the schema without replacing it, so 4 is appropriate.

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 defines the resource ('A v2 app's grant links') and enumerates the three actions with specific verbs: mint, list, and revoke. It distinguishes itself from sibling tools by focusing on capability URLs and custom role grants, with a clear explanation of what a grant link is and does.

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?

The description gives clear context on when to use each action and explains key modes (once vs multi), but it does not explicitly name alternative tools or state 'use members instead.' It does provide a useful exclusion: 'A grant does not escalate to owner, member or agent,' which helps scope its usage.

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