slack_set_channel_purpose

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

With no annotations, the description bears full responsibility for behavioral disclosure. It fails to state that the tool modifies a channel (destructive), requires permissions, or what the outcome is. This is a critical 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?

The description is short but includes unnecessary routing details (e.g., the /api/tools/invoke path) while missing essential functional information. It could be more concise and focused by stating the tool's actual purpose.

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?

Given the simplicity of the tool (one parameter, no annotations), the description is woefully incomplete. It does not explain what the tool does, expected input structure, or return values, even though an output schema exists. The agent cannot effectively use this tool based solely on the description.

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's single parameter 'arguments' has 0% description coverage and only a default of '{}'. The description adds only 'JSON string of arguments' with no details on expected structure or keys, offering minimal value beyond the schema.

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 repeats the tool name ('set_channel_purpose') without explaining that it sets the purpose of a Slack channel. It is essentially a tautology and provides no differentiation from sibling tools like slack_set_channel_topic.

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 offers no guidance on when to use this tool versus alternatives. It does not mention prerequisites, context, or how it compares to other Slack channel modification tools.

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