contacts_update_contact

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

The annotations already declare the operation to be non-read-only, idempotent, and non-destructive, but the description adds nothing beyond that. It does not explain what happens during the update, such as whether fields are overwritten individually or all at once. With annotations present, the description still contributes no additional behavioral context.

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 two-word description is under-specification, not conciseness. It is not front-loaded with essential information because it contains none. There is no structure or prioritization of the most important aspects an agent needs to know.

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?

Given the high complexity (21 parameters, nested objects, no output schema), this description is grossly incomplete. An agent cannot infer how to call this tool correctly, what to pass, or what to expect. It is fundamentally inadequate for successful 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 schema covers only 19% of parameters with descriptions, and the tool description mentions none of them. For a tool with 21 parameters, the description should at least hint at common fields or usage patterns, but it does not. It fails to compensate 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 'Update Contact' essentially restates the tool name, adding no new information about what the update entails. It is a tautology that fails to distinguish this from sibling tools like contacts_upsert_contact or contacts_create_contact. The verb and resource are clear, but no specifics are provided.

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 guidance on when to use this tool versus alternatives such as upsert or create. The description offers no context on prerequisites, scenarios that warrant an update, or when another contact tool would be more appropriate. An agent is left guessing about tool selection.

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