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

Annotations already establish readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds genuinely useful behavior beyond that: it enumerates what comes back (role hypotheses, anti-champion warning signs, a development path, and what to give the champion) and explicitly caveats "These are roles to test, not named people," which prevents misreading the output as real contacts. It does not discuss depth of analysis or determinism, keeping it below 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 sentences, front-loaded with the purpose, then inputs, then outputs — a sensible order with no repetition of the title. Some phrasing is conversational ("who inside the buyer will push for you") but it carries meaning rather than filler.

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?

There is no output schema, so the description must explain returns, and it does so thoroughly by listing the role types, anti-champion signals, and the champion development path. Combined with required inputs and the roles-not-people caveat, an agent has everything needed to call it and interpret the result.

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 every parameter is already documented in the schema, including the enum for your_sector. The description only restates the parameter list (product, problem, company name, target company type, price point, sector) without adding syntax, formatting, or interaction guidance, so 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?

The description opens with a concrete outcome — "Helps you decide who inside the buyer will push for you" — and then names the artifact produced (champion, economic buyer, technical influencer, reviewers, daily users, anti-champion warning signs). That is enough to distinguish it from siblings like impact_anchor_market or impact_craft_message without opening schemas. It stops short of explicitly naming a sibling it is not, so it lands at 4 rather than 5.

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 describes the input situation ("You give what your product does and the problem it solves, plus optional company name, target company type, price point and sector"), which implies when the tool applies. However, there is no explicit when-not guidance and no routing to alternatives among the impact_* siblings, so the agent must infer positioning.

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