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

Annotations already flag the write/destructive/non-idempotent profile, and the description adds genuinely new operational context: size ceiling, accepted MIME types, base64 transport, auth scope, token expiry window, and a consumer-consent policy. It does not explain what happens on success or why the operation is destructive, keeping it below a 5.

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, zero filler, with the most decision-critical facts (what it accepts, size, dependency) front-loaded. Every clause earns its place.

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 single-parameter upload tool with annotations covering the safety profile and no output schema, the description covers prerequisites, limits, consent policy, and encoding. The only gap is post-upload behavior (return value, duplicate handling despite non-idempotentHint), which is 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 coverage is 0% for the single file_base64 parameter, so the description must compensate — and it does, specifying encoding (base64), accepted formats, and the 5 MiB cap. It does not describe the exact base64 payload shape or whether a filename accompanies it, so not a 5.

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?

Specific verb+resource (upload evidence) with tight qualifiers: private, consumer-authorized, PDF/PNG/JPEG, max 5 MiB, base64. This clearly distinguishes it from siblings like submit_review or prepare_review without opening any 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 description states a hard prerequisite ('Requires review:prepare via OAuth or a one-hour manual Bearer token'), which tells the agent this tool belongs to the review-preparation flow. It does not name an alternative tool or an explicit when-not-to-use case, so it falls short of a 5.

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