update_contact

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

No annotations are provided, so the description carries full burden for behavior. It only states 'update' without disclosing whether it performs a full replacement or partial update, any permission requirements, side effects, or return behavior. The phrase 'existing contact' mildly implies it does not create new contacts, but this is minimal.

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 is a single short sentence that is easy to read, but it is under-specified rather than genuinely concise. It does not add information beyond a restatement of the tool name, offering little value per sentence. While not verbose, it lacks the front-loaded context that would elevate 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?

With 8 parameters, no annotations, and no output schema, the description is severely incomplete. It fails to explain which fields are updatable, whether the update is partial or full, what the response includes, or any required permissions. The tool has enough complexity that the one-line description leaves the agent without critical context.

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?

The input schema has 100% coverage with descriptions for all 8 parameters, so the schema already documents parameter meanings. The description adds no extra semantic information beyond the generic word 'details', matching the baseline for high schema coverage.

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 states 'Update an existing contact's details' with a specific verb (Update), resource (contact), and scope (existing). This clearly distinguishes it from sibling tools like create_contact or delete_contact, and from updates to other resources (update_client, update_event).

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 implies usage for modifying an existing contact but provides no explicit guidance on when to use this tool vs alternatives (e.g., create_contact for new contacts) or any preconditions. It does not mention what fields can be updated or how to identify the contact, relying entirely on the schema.

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