insert_contact

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool inserts a contact and returns a success or error message, but fails to mention critical details like whether this requires specific permissions, if it's idempotent, what happens on duplicate entries, or any rate limits. This is a significant gap for a mutation tool with zero annotation coverage.

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 highly concise and well-structured, using a brief purpose statement followed by bullet points for args and returns. Every sentence earns its place without redundancy, making it easy to parse and front-loaded with essential information.

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 tool's complexity (a simple mutation with 2 parameters), the description covers the basic purpose and parameters adequately. However, with no annotations and an output schema that only indicates a string return, it lacks details on behavioral traits and error handling, making it minimally viable but incomplete for safe and effective use.

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 explicitly lists both parameters ('name' and 'number') with their types and meanings, adding clear semantics beyond the input schema, which has 0% description coverage. This compensates well for the schema's lack of detail, though it could further clarify constraints like format or length.

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 action ('Insert a new contact') and the resource ('contact'), which is specific and unambiguous. However, it does not differentiate from sibling tools like 'delete_contact' or 'get_contacts' beyond the basic verb, leaving room for improvement in distinguishing its exact role among alternatives.

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 provides no guidance on when to use this tool versus alternatives such as 'delete_contact' or 'get_contacts'. It lacks context about prerequisites, scenarios, or exclusions, leaving the agent to infer usage based solely on the tool name and basic purpose.

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