Set Primary Person Name

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

Beyond the annotations (readOnlyHint=false, destructiveHint=false), the description adds real behavior: the name change 'refresh[es] slug' and 'by default preserves the old name as a former_name alias.' It also discloses operational constraints, '$0.10; API key required,' and classifies the mutation as 'bounded.' No conflict with 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 wastes no words: purpose, default behavior, and alternative preference are packed into four short sentences. The most important scoping information is front-loaded, with cost/auth appended as a parenthetical.

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 5-parameter mutation with an output schema and annotations, the description covers purpose, side effects, alternative workflows, default behavior, auth, and cost. Nothing required to invoke it correctly is missing; the output schema can explain return values.

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 coverage is only 40%, with descriptions only for request_id/idempotency_key. The description compensates for the main optional flag by explaining the default for preserve_old_name_as_alias, and it clarifies that the supplied name is the new canonical name. It leaves person_id and request_id semantics implicit, but those are largely inferable from tool name and schema descriptions.

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 action and target: 'Rename a CRM contact’s canonical name and refresh slug,' which is clearly distinct from adding an alias or merging people. It also contrasts with the create+merge workflow, making the tool's specific job unambiguous among siblings like add_person_alias, update_person, and merge_people.

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 an explicit condition: 'Prefer this over create+merge for spelling fixes,' which tells an agent when this tool is the right choice. The default-preservation behavior also signals that rename is the intended lightweight operation rather than a destructive merge. This is sufficient routing guidance given the surrounding sibling tools.

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