slack_list_messages

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

With no annotations, the description carries the full burden of behavioral disclosure. It doesn't mention pagination behavior, ordering, authentication needs, or what 'recent' means, leaving the agent to infer these details from the schema. For a read operation, this is a notable gap.

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, focused sentence with no superfluous words. The description is immediately understandable and follows the pattern of front-loading the verb and resource.

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 tool with three parameters and full schema coverage, the description is minimally sufficient. However, it omits details about pagination, return format, and time bounds that would be valuable given the lack of an output schema and annotations. It is complete enough for a simple list operation but could be richer.

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 coverage is 100%, so the baseline is 3. The description adds the notion of 'recent' which suggests ordering, but does not elaborate on parameter specifics beyond what the schema already provides. It is adequate but not compensatory.

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 ('List') and resource ('recent messages in a channel'). While it doesn't explicitly differentiate from sibling tools like slack_get_channel or slack_list_channels, the resource is distinct and the purpose is 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?

No guidance is provided on when to use this tool instead of alternatives, nor are there any exclusions or prerequisites. The description merely states what the tool does without helping the agent decide between this and similar Slack tools.

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