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

With no annotations, the description carries the behavioral burden. 'Read' signals a non-destructive operation, and the state note reveals that submitted/unhandled is the default filter. However, it does not disclose whether reading changes message state, ordering, pagination, or access requirements.

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?

Two short sentences front-load the purpose and then give the only essential state detail. Every word earns its place; no redundant schema repetition.

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?

The tool has no annotations, no output schema, and no schema descriptions, so the minimal text leaves significant gaps: expected return shape, whether messages are marked handled, and limit semantics are unclear. It is enough for a trivial no-arg call, but not for robust 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?

Schema description coverage is 0%, so the description must explain both parameters. It explains state values ('submitted' and 'all') and the default, but says nothing about 'limit', leaving its meaning and constraints to inference.

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 names a specific operation ('Read') and a clear resource ('your agent's incoming DMs'), which distinguishes it from siblings like send_dm or reply. It could further differentiate itself from get_conversation or read_digest, but the resource is specific enough.

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 gives no explicit when-to-use guidance or alternatives, and no exclusions. The state=submitted hint explains default filtering but not when to prefer this tool over get_conversation or read_digest.

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