Get a contact

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is fully covered. The description adds nothing beyond that — no note on error behavior for an unknown contactId, no indication of what "full" includes relative to list results.

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?

A three-word fragment is free of filler, which is appropriate for a trivial single-parameter read, but the brevity is under-specification rather than true conciseness — it omits information rather than compressing it.

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 simple 1-param read with full annotation coverage and 100% schema coverage, the minimum an agent needs is present. However, with siblings like find_contacts and list_contacts in the same family, the description should have clarified that this requires an existing contactId and returns one record.

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%, and contactId is documented in the schema as the EndUser ID, so the baseline is 3. The description adds no syntax, format, or lookup-scope detail beyond what the schema already provides.

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?

"Full contact record" contains no verb and effectively restates the title "Get a contact"; the only added nuance is the word "full." It does not distinguish this tool from siblings like find_contacts, list_contacts, or get_customer.

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?

There is no when-to-use guidance, no mention of prerequisites (e.g. needing a valid contactId), and no reference to the obvious alternatives find_contacts or list_contacts. The agent must infer that this is an ID-based single-record lookup from the schema alone.

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