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

Annotations already provide readOnlyHint=false, openWorldHint=true, idempotentHint=true, destructiveHint=false. The description adds valuable behavioral context: it validates without executing contents, freezes bytes into a private immutable snapshot, rejects unsafe archives, and returns the SHA-256. This goes beyond what annotations state, covering safety and idempotency implications without contradicting them.

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 that front-load the core action and then provide safety and return details. Every sentence earns its place; it is efficient and well-structured. It could be slightly more explicit about the order relative to other tools, but overall it is concise and clear.

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?

Given the tool has 2 parameters (fully documented), no output schema, and annotations covering safety, the description provides sufficient context. It explains the main operation, safety constraint, return value, and failure condition. It doesn't detail error formats or edge cases, but for a tool in a sequential flow (after prepare_review_upload), it is reasonably complete.

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% – both upload_id and upload_token have clear descriptions indicating their roles. The description does not add any extra meaning about these parameters. Baseline 3 applies since the schema fully documents them; no additional value is provided by the description.

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 action: validate a ZIP and freeze it into an immutable snapshot, returning SHA-256. It clearly identifies the resource (uploaded archive) and the verb (validate/freeze). It implies a step after uploading but does not explicitly name sibling tools like prepare_review_upload or submit_project_review, so it lacks explicit differentiation.

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 phrase 'After uploading' gives clear contextual guidance on when to use this tool, implying it should be called after prepare_review_upload. However, it does not explicitly state when not to use it, nor does it mention alternatives or exclusions. The usage context is clear but not exhaustive.

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