update_contact

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

With no annotations, the description carries the full burden for behavioral disclosure. It only says 'Update an existing contact' and does not mention replacement semantics for tags, partial vs. full update behavior, whether the contactId is required, or any side effects.

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 sentence with no fluff, but it essentially restates the tool name, offering zero additional structure or information. It fails to earn its place as a meaningful description.

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?

This is a parameterized update tool with no output schema and no annotations. The description fails to communicate return values, error behavior, or prerequisites, leaving the agent without essential context for correct invocation.

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 covers only 33% of parameters with descriptions (tags and contactId). The description adds no parameter meaning, and the semantics of email, phone, firstName, and lastName remain unclear beyond their names. No compensation for the low 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 the verb 'Update' and the resource 'contact', making the basic action clear. However, it does not specify which fields are updatable or distinguish itself from siblings like add_tags, which also modifies contact data. It is somewhat redundant with the tool name.

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?

No guidance is provided on when to use this tool versus alternatives like create_contact or add_tags. The description implies use when updating a contact but does not state prerequisites, exclusions, or context for selection.

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