slack_delete_message

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

Annotations already declare destructiveHint=true and idempotentHint=false, so the safety profile is covered structurally. The description adds real value beyond them: the irreversibility warning, the ownership restriction that even an admin token cannot bypass, and the required OAuth scope. It doesn't cover response shape or error behavior, but that is partly handled by the output 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?

Three short sentences, each carrying distinct information: what it deletes, the ownership/auth constraint, and the irreversibility. Everything is front-loaded with zero filler.

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?

Annotations and the output schema cover the safety profile and return values, so the description doesn't need to. However, with 0% schema coverage on three parameters, the description leaves a meaningful gap around how to identify the target message—the single most error-prone part of this call.

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% and none of the three parameters (ts, workspace, channel_id) are explained in the description. Notably, 'ts'—the message timestamp identifier, which is a Slack-specific concept an agent could easily get wrong—is left entirely undocumented in both places.

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?

States a specific verb+resource ('Delete one of YOUR messages') and names the underlying Slack API call plus required scope (chat.delete, chat:write). Ownership scoping is spelled out clearly. It doesn't explicitly differentiate from the closest sibling slack_edit_message, but the verb makes the distinction obvious 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?

'Delete one of YOUR messages' establishes the applicable context, and 'Messages by others are refused even with an admin token' functions as an explicit when-not constraint. It doesn't point to an alternative tool, but the boundary is unambiguous for this operation.

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