send_dm

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

No annotations are provided, so the description carries full burden. 'Send a direct message' implies a write operation, but it doesn't disclose behavioral traits like authentication requirements, rate limits, message length constraints, delivery confirmation, or whether messages are ephemeral. The description is minimal and lacks crucial operational context.

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 at just 6 words, front-loading the core functionality with zero wasted words. Every word earns its place in conveying the basic purpose.

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 with no annotations, 2 undocumented parameters, and an output schema (which helps but doesn't replace description), the description is inadequate. It doesn't address authentication needs, error conditions, or provide enough context for reliable tool invocation despite the output schema's presence.

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?

With 0% schema description coverage for both parameters, the description adds no semantic information about 'participant_id' (what format, how to obtain it) or 'text' (character limits, formatting options). The description doesn't compensate for the complete lack of schema documentation, leaving parameters essentially unexplained.

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 ('direct message to a user'), making the purpose immediately understandable. However, it doesn't differentiate from sibling tools like 'post_tweet' or 'create_thread' that also involve sending messages but in different contexts.

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. With sibling tools like 'post_tweet' for public messages and 'get_dm_conversations' for retrieving DMs, there's no indication of when direct messaging is appropriate versus other communication methods.

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