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

Annotations establish the operation is a non-read, non-destructive, non-idempotent mutation, and the description adds genuine context beyond that: a PENDING suggestion is written and only on acceptance is the milestone flipped to completed. It does not cover the reject path, permission requirements, or resubmission behavior.

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 its approval-gated nature, then the state transition, then the usage cue. No filler or repetition of the title.

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 two-parameter, no-output-schema mutation with annotations already covering safety, the description supplies the essential two-phase behavior an agent needs. Remaining gaps (reject/withdraw behavior, permissions) are minor.

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 description coverage is 100% and both parameters are fully documented in the schema, including 'shown to the reviewer' and 'must be visible to the caller'. The description adds no syntax or format detail beyond that, so the baseline 3 applies.

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 (propose) and resource (milestone completion) plus the governing constraint 'for human review', which cleanly separates it from a direct mutation like update_milestone. An agent can tell what it does and that it is an approval-gated proposal without opening 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?

The final sentence gives an explicit trigger condition ('when a milestone looks reached but you want a human to confirm the sign-off'), which is clear usage context. It stops short of naming alternative siblings or stating when not to use it (e.g. when auto-approval or direct update_milestone is preferred).

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