update_contact

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

With no annotations, the description must disclose behavioral side effects, but it only states the update action and prerequisite. It does not mention that updating tags replaces the entire list, the idempotency key behavior, or any mutation risks. This lacks transparency for a write operation.

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 short sentences, front-loaded with the primary purpose and a key prerequisite. No fluff, every word earns its place.

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 tool with 11 parameters, no annotations, and no output schema, this description is incomplete. It does not mention partial update semantics, tag replacement, confirmation requirements, idempotency, or return values, leaving critical behavioral and usage gaps.

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 45%, so the description must compensate. It only elaborates on contact_id, telling users to provide it from search_contacts, but does not explain the other 10 parameters (e.g., tags replacement, confirmed requirement). The description adds minimal value beyond the schema.

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 clearly states 'Update an existing contact's fields' with a specific verb and resource, distinguishing it from sibling tools like create_contact, delete_contact, and get_contact. This is an exact, non-tautological purpose.

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 provides clear usage context by requiring contact_id and explicitly recommends using search_contacts to find it. This is actionable guidance, though it does not explicitly list exclusions or alternative tools, it is sufficient for the resource.

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