set_channel_favorite

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

With no annotations provided, the description must disclose behavior, but it only states the binary action. It doesn't clarify whether this modifies state persistently, requires special permissions, or triggers notifications. It doesn't contradict anything (no annotations), but it's minimal.

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, clear sentence that is efficient and front-loaded. It covers the essential action without waste, though it could add a bit more context in a second sentence.

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 only 2 parameters with full schema coverage, but no output schema and no annotations. The description is complete for basic understanding, but lacks guidance on behavior, errors, or effects, which is a notable gap for a mutation tool in a large toolset.

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%: 'favorite' is described as 'true to mark as favorite, false to unmark' and 'channel_id' as 'Channel ID'. The description adds almost nothing beyond the schema, so baseline 3 is appropriate.

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 'Marks or unmarks a channel as favorite' uses a specific verb ('marks/unmarks') and resource ('channel'), clearly indicating the action. It distinguishes from sibling tools like set_conversation_favorite by targeting channels specifically, though it doesn't explicitly name the alternative.

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 implies usage for toggling favorite status on a channel, and the schema requires both channel_id and favorite. However, it lacks explicit guidance on when to use vs. alternatives (e.g., set_conversation_favorite), or any context like prerequisites or side effects.

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