Dm Channel For User

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

With no annotations provided, the description carries the full behavioral burden. It explicitly notes the tool returns None if no DM channel exists, and the verb 'Find' implies a non-mutating read operation, adding valuable behavioral nuance beyond the schema.

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?

A single sentence that front-loads the verb and result, includes the None case, and contains no filler. Every word earns its place.

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 simple one-parameter lookup tool, this describes the input, the output, and the no-result case. It lacks explicit read-only or error-behavior statements, but the scope is simple enough that nothing critical is missing for invocation.

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 schema has one parameter, user_id, with zero description coverage. The description mentions 'a given user_id,' linking the parameter to its purpose. While it adds no extra formatting or validity constraints, for a simple integer ID this is sufficient to invoke correctly.

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 specific operation: finding the 1:1 DM channel_id for a given user_id. It distinguishes itself from siblings like list_channels and find_user by naming the exact resource (DM channel) and the lookup key (user_id).

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: use this tool when you need a user's DM channel_id. It does not explicitly name alternatives or exclusions, but its purpose is unambiguous enough that an agent can infer when to select it over list_channels or find_user.

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