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

Annotations set readOnlyHint=false, destructiveHint=false, openWorldHint=false but say nothing about billing. The description adds a concrete and important behavioral fact: "Charges 1 credit only when an email is found." That conditional cost model is exactly the kind of detail annotations cannot convey. Auth requirements and rate limits are still unstated.

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?

Two sentences, fully front-loaded: capability first, cost model second. No filler, no restated schema detail.

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?

An output schema exists, so return values need not be explained, and the billing note covers the main hidden behavior. What remains thin is any guidance on which input combination to prefer and what happens on a miss, which matters for a tool whose cost is conditional.

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 each parameter (name, domain, linkedin) is already documented with format examples. The description only restates the two combination modes, adding no syntax or constraint detail beyond the schema, so the 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?

States a specific verb and resource ("Find a person's work email") and names the two accepted input modes, which is more than a title restatement. It does not, however, distinguish itself from near-siblings like persons_lookup or persons_search, so an agent must still infer which lookup tool to pick.

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 the two valid input paths (LinkedIn URL, or name plus domain), which implies usage. It never states when to prefer this over persons_lookup, persons_find_phone, or organizations_find_decision_maker, and gives no exclusions or prerequisites.

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