list_channels

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

With no annotations provided, the description carries the full behavioral burden. It clearly conveys the read-only listing behavior and explicitly includes private channels. It does not mention pagination, required OAuth scopes, or the fact that private channel visibility may be limited to channels the app has access to, but the core semantics are not misleading.

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 a single, front-loaded sentence with no filler. It states the resource, scope, and channel types in a compact way that an agent can parse quickly.

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?

The tool has no required parameters and all optional parameters are fully described in the schema, so an agent can invoke it correctly from the description alone. It lacks an explicit output-format hint and pagination note, but for a simple read-only list operation this is a minor gap.

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?

All four parameters are fully documented in the input schema (100% coverage), so the description does not need to add parameter-level detail. The description adds no extra semantics beyond the schema, so the baseline score of 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?

The description uses a specific verb ('List'), a clear resource ('channels'), and a well-defined scope ('in the Slack workspace (public and private)'). It clearly distinguishes itself from siblings like get_channel_info (single channel) and list_user_channels (user-specific channels), even without naming them.

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 phrase 'all channels in the Slack workspace' implies workspace-wide enumeration, which indirectly contrasts with list_user_channels. However, it does not explicitly state when to prefer this tool over alternatives or mention exclusions such as archived channels.

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