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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is covered. The description adds genuine extra context: it is a self-service grantee action and the server verifies grantee authorization, which implies a permission precondition not expressed in the schema. It stops short of describing what the grantee loses (e.g., retained fact data or re-access options), so it is not fully complete.

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?

Three short sentences, front-loaded with the action and effect, then precondition, then the disambiguation to the sibling tool. Every sentence earns its place with no padding.

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 one-parameter tool with no output schema, the description covers action, actor, authorization verification, and the boundary with revoke_grant, while annotations cover destructiveness and idempotency. The main gap is the post-condition for the grantee (what access or data is affected after leaving), which is left implicit.

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?

There is a single parameter with 100% schema description coverage ('UUID of the active grant to leave'), so the schema already carries the semantics. The description adds no format, sourcing, or lookup guidance for grant_id beyond what the schema states, making the baseline 3 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?

States a specific verb+resource ('Leave an active namespace grant') plus the role it acts as (the grantee) and the effect (stop using shared namespace). It also explicitly distinguishes itself from the sibling revoke_grant, so an agent can route correctly without opening either 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?

Provides explicit when-to-use ('as the grantee... stop using shared namespace') and when-not-to-use with a named alternative ('Grantors who want to cut off a collaborator must use revoke_grant'). No inference is required to pick between the two tools.

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