List connected channels

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

Annotations already provide readOnly, idempotent, and non-destructive hints, so the safety profile is covered. The description adds workflow context (call first, pass result as account) and clarifies that all connected channels are returned, which is useful beyond annotations.

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 sentences, both purposeful and well-ordered. The main behavior is stated first, followed by a practical usage note. No filler or redundancy.

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 zero-parameter, read-only tool with rich annotations, the description fully covers what the agent needs: what to call, when to call it, and what to do with the result. No output schema is present, but the returned names are self-explanatory.

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 tool has zero parameters, so there are no semantics to clarify beyond the schema. The baseline for 0 params is 4, and the description add no param information because none is needed.

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?

Description states a specific verb ('List') and resource ('every YouTube channel connected to this server'), clearly identifying the tool's function. It also distinguishes itself from siblings by positioning it as the entry point that returns account names for use by other tools.

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 gives clear usage context: call first when more than one channel may be connected, then use the returned name as the `account` parameter elsewhere. It does not explicitly state when not to call it, but the condition is specific enough for an agent to decide.

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