send_message

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

With no annotations provided, the description alone must convey behavioral traits. It only states the action, implying a side effect but omitting critical details such as authentication requirements, restrictions on recipients, or error/response behavior. This is a significant gap for a mutating tool.

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, clean sentence that immediately conveys the tool's purpose. It is appropriately sized, with no unnecessary wording, and fully front-loaded. Although more content could be added to address other dimensions, the structure itself is excellent.

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 lack of annotations, the presence of a similarly named sibling ('send_inbox_message'), and three required parameters, the description is insufficiently complete. It does not explain the tool's role relative to siblings, what constitutes a 'direct message,' or any operational context such as success/failure output. The single-sentence description is too minimal for a tool with this complexity and ambiguity.

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 all three parameters with descriptions, so the baseline is 3. The tool description adds no further meaning and, notably, leaves the distinction between 'profile_id' and 'recipient_url' ambiguous. While the schema definitions are present, the description does not clarify the relationship or intended usage, but it also doesn't detract from the schema's 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 verb 'send' and the resource 'direct message to a LinkedIn connection,' making the core purpose understandable. However, it does not differentiate from the sibling tool 'send_inbox_message,' which likely performs a similar action, so it misses the highest mark.

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 'send_inbox_message' or any other alternative. The description simply states the action without indicating prerequisites, exclusions, or context, leaving the agent uncertain about the appropriate scenario.

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