Send Message

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

Beyond the annotations (destructiveHint, openWorldHint), the description adds the specific constraint that the recipient must be directly messageable, which is a key behavioral limitation. It also reiterates the write condition tied to confirm_send, giving the agent a clearer picture of side effects. This adds value beyond the structured annotations.

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 two sentences, with the primary action front-loaded. Every sentence serves a purpose: the first states what the tool does, and the second provides essential conditions. There is no redundancy or filler, making it highly efficient.

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 output schema, full parameter descriptions, and annotations, the description provides sufficient context. The key limitation (messageability) is explicitly stated, and the write condition is clarified. While it could have elaborated on failure modes or alternative tools, the overall tool definition is adequately complete with the schema and annotations covering the rest.

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?

Schema description coverage is 100%, so the baseline is 3. The description does not add information about parameters beyond what the schema already explains (e.g., confirm_send's role is fully documented). While the main description mentions confirm_send, it adds no new semantic detail, so no bonus is warranted.

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's action: 'Send a message to a LinkedIn user.' This uses a specific verb ('send') and resource ('message to a LinkedIn user'), distinguishing it from sibling tools like get_inbox or search_conversations. No other tool in the sibling list performs a send action, making the purpose unambiguous.

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 clear context by stating that the recipient 'must be directly messageable from the profile page,' which indicates a precondition for use. It also clarifies that the operation is a write only when confirm_send is True. However, it does not explicitly name alternatives or when to prefer another tool, so it stops short of a 5.

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