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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds behavioral context by explaining the filtering scope ('tied to a specific project') and the expected result contents ('star rating, customer name, project name, and quote text'). It does not contradict the annotations.

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 short and front-loaded, with the core action in the first sentence. The phrase 'from the testimonials table' is slightly redundant given the tool name, but the rest of the sentences each earn their place by adding return fields and usage context. It could be tightened, but it is not bloated.

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 that all four parameters are documented with descriptions, annotations cover safety/idempotency, an output schema exists, and the description covers use case and alternatives, nothing critical is missing. An agent can correctly select and invoke this tool without additional information.

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%, so the parameters are already fully documented. The description's mention of 'by slug or keyword' slightly reinforces the relationship between projectSlug and keyword, but it does not add meaning beyond what the schema provides. The baseline of 3 is 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?

The description opens with a specific verb and resource: 'Get customer testimonials tied to a specific project'. It clearly defines scope (by slug or keyword) and names the return fields, so an agent knows what the tool does. It also explicitly distinguishes itself from the sibling 'list_reviews', reinforcing purpose clarity.

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 gives a concrete use case: 'Use to source social proof or case-study quotes for a particular job.' It also provides an explicit when-not-to-use condition with a named alternative: 'For unfiltered reviews, use list_reviews.' This directly helps an agent choose between this tool and list_reviews.

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