Create a new Slack channel for sales collaboration by specifying a unique name and whether it should be private.
Create a channel. Slack refuses a name that is already taken.
| Name | Required | Description | Default |
|---|---|---|---|
| name | Yes | The channel name, lowercase, without spaces or periods and at most 80 characters. Slack answers `name_taken` if it already exists. | |
| isPrivate | No | Create a private channel rather than a public one. |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false and openWorldHint=true, so mutation and external-effect semantics are covered. The description adds a useful behavioral note about name collisions, but omits visibility defaults, permissions, and rate limits.
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 with the core action front-loaded and no filler. It is tightly sized for a two-parameter tool, though the second sentence restates the schema's name_taken note.
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 mutation with no output schema and fully documented parameters, the description is adequate but thin on visibility semantics and confirmation behavior. Nothing critical is missing, but an agent gets just the minimum.
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 100%, so both parameters are already documented in the schema, including the lowercase/80-char rules and the name_taken behavior. The description adds no syntax or format detail beyond the schema, so baseline 3 applies.
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 clear verb+resource ('Create a channel') that an agent can distinguish from siblings like slack_chat_post_message. It does not explicitly name a sibling or scope, but 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?
There is no when-to-use guidance, no mention of prerequisites (auth scopes, workspace), and no routing to alternatives. The agent must infer that this is for creating rather than posting to a channel.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.