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

The description goes well beyond the annotations by explaining that disabling silently stops delivery, enabling without credentials has no effect, changes affect live campaigns/autopilot, and repeating the same state is safe. It also notes the API key requirement and aligns with openWorldHint via real-world delivery impact.

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 compact but information-dense. Every sentence serves a purpose: purpose, impact, caveats, usage guidance, idempotence, and authentication. It is well-structured and front-loaded with the primary action.

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 two-parameter mutation tool with no output schema, this description is fully complete. It covers what the tool does, when to use it, what side effects to expect, prerequisites, idempotence, and auth requirements, leaving no important operational question unanswered.

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 coverage is 100% and the parameter descriptions are already clear, so the baseline is 3. The description adds meaningful behavioral context for enabled: true requires configured credentials to work and false silently stops delivery, while also clarifying that each call handles only one channel. This adds value beyond the schema, though the core parameter meaning is still schema-driven.

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 opens with a specific verb phrase, 'Turn one outreach channel on or off,' and names the exact channels (WhatsApp, SMS, push). It clearly distinguishes update_channel from the read-oriented sibling get_channels_status by focusing on state mutation and delivery impact.

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 explicitly tells the agent to 'Call get_channels_status first to see where things stand,' establishing a clear prerequisite and alternative tool. It also gives practical guidance about live campaigns, autopilot runs, credential requirements, and the one-channel-per-call constraint.

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