Send Message

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

Beyond the annotations (destructiveHint and openWorldHint), the description clarifies that the write happens only when confirm_send is True, which is a safeguard. It also adds the requirement for direct messageability. This extra context helps the agent understand the tool's behavior without relying solely on 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 extremely concise: two sentences that immediately state the purpose and key constraint. It front-loads the core function and avoids unnecessary elaboration, making it easy for an agent to scan.

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 write operation, the description covers the essential behavioral prerequisites (messageability, confirm_send flag) and relies on the schema for parameter details. It does not mention authentication or output, but those are supplied by annotations and the presence of an output schema. The description is adequate for the tool's complexity.

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 already provides complete descriptions for all four parameters (100% coverage), so the tool description does not need to repeat them. It does not add any additional meaning beyond what the schema gives, which is the baseline expectation.

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 (send) and target (a LinkedIn user), with an important qualifier about direct messageability from the profile page. This establishes the tool's core purpose and differentiates it from read-only LinkedIn tools by explicitly labeling it a write operation.

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 a prerequisite (the recipient must be directly messageable) and notes that the send only occurs when confirm_send is True, implicitly advising caution. However, it does not mention when to choose this tool over alternatives like connecting first or using the inbox, so guidance on context and exclusions is limited.

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