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

Annotations already declare idempotentHint=true and destructiveHint=false, so the safety profile is largely covered. The description adds real context beyond that: the write is gated on explicit public consent, it has 'No payment effect', and replay requires reusing the same key and body — a concrete operational instruction not present in the annotations or schema.

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?

Five tight sentences with no filler, and the most consequential constraint (public consent, secret handling, no payment effect) comes first. The telegraphic fragments ('example_id is free-example linkage only') are dense but not padded.

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?

No output schema exists, so the description needn't cover returns, and it does address the nested purchase_proof object and idempotency behavior. However, for a 10-parameter write tool with 10% schema coverage, it omits any explanation of outcome, version, and product_id, leaving the agent to guess at several fields.

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 only 10% across 10 parameters, so the description carries a heavy burden. It explains purchase_proof's secret semantics, example_id's limited role, and idempotency replay, but leaves outcome, version, product_id, and rating/message meaning entirely to the schema. Partial compensation for a very sparse schema.

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 ('Publish your display name, text and optional rating') and scopes it to a public consent flow. It is distinguishable from siblings like list_reviews or get_review, but it never contrasts itself with leave_feedback, which is the closest overlapping surface.

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?

It gives conditional guidance for purchase_proof ('uses the caller-kept secret committed to the original paid request; never a receipt ID alone') and for replay ('Keep the same key/body'), which is useful. It gives no when-to-use guidance relative to the other review-shaped siblings, so usage is only implied.

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