delete-message

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

With no annotations, the description carries the full burden and does well: it flags the destructive nature, requires explicit user confirmation, and advises confirmation of the id. It doesn't cover all edge cases (e.g., attachments), but it covers the critical safety aspects. Slightly more detail on reversibility would push it higher.

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 concise and well-structured using labeled sections (Use when, Returns, Do not use when, Safety). Every sentence adds value, with no fluff or 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?

For a simple one-parameter destructive action with an output schema, the description covers all necessary context: when to use, what happens, and safety checks. It also differentiates from similar tools, making it complete for agent use.

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?

There is only one parameter, id. The description explicitly says 'by id' and clarifies it's a message id. The schema provides a pattern, which helps further. The description adds enough context for the agent to understand the parameter's role without redundancy.

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 it deletes a single message by id and moves it to Trash. It distinguishes from siblings by explicitly pointing to batch-delete-messages and move-message, 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 explicit guidance with 'Use when' and 'Do not use when', naming alternatives (batch-delete-messages, move-message). It also recommends verifying the id first, which is actionable for agent decision-making.

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