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

Annotations already signal read-only and non-destructive, but the description adds the side effect of 'minting a handle' and confirms it writes no state, which enriches understanding beyond the 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 concise sentences, front-loaded with the primary action and output, then a clear usage directive. No waste.

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 tool with a descriptive output schema, it covers the essential workflow context. It could mention what 'subsequent pipeline tools' are explicitly, but it lists enough to guide.

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?

Has zero parameters, so the schema is trivially complete. The description adds the critical semantic that the output is a pipeline_id to be used elsewhere, which is beyond structural schema.

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 specific verb and resource: starts a pipeline and returns an id. Distinguishes itself by tying to the fax workflow and listing sibling tools it should be used with.

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?

Gives explicit when-to-use (calling first when sending a fax) and explains how to use the output (pass id to subsequent pipeline tools, optionally to list-numbers/list-contacts), which routes the agent clearly.

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