reach_updateAContactV1

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

With no annotations, the description carries the full burden and discloses key behavioral traits: only properties in the body are changed, null clears values, and the response only includes core attributes. This goes beyond a generic 'update' and gives the agent concrete expectations.

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?

Three short, front-loaded sentences with no redundancy. Purpose first, followed by critical behavioral details and a pointer for additional data retrieval.

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 9-parameter tool without output schema or annotations, the description covers partial update behavior, null handling, response scope, and directs to a GET method for full data. It lacks error handling and validation details but is otherwise complete enough for an agent to invoke correctly.

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 description adds meaningful semantics for the `fields` parameter (omit vs empty array) and explains that null clears scalar properties. The schema descriptions are largely tautological ('name parameter'), so the description's added value is significant despite 100% 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 clearly states the tool updates a contact's attributes and custom field values, with a specific verb and resource. It distinguishes from related siblings like reach_createANewContactV1 and reach_deleteAContactV1 by the update action.

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?

Provides clear context for partial updates and null clearing, helping the agent understand when to use this tool. It does not explicitly name alternative update tools, but it does point to a GET endpoint for reading back extended data, offering reasonable guidance.

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