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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds contextual scope (the handbook corpus) but no further behavioral traits such as ordering, pagination, or authentication requirements. It neither contradicts nor significantly extends 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?

The description is two sentences long, with the main action and scope in the first sentence and usage guidance in the second. Every sentence earns its place, and the key information is front-loaded.

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 simple list tool with zero required parameters and an output schema present, the description fully covers what the tool does, what the list contains, and when to use it. No critical information is missing.

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% for the single optional 'locale' parameter, which includes an enum and description. The tool description adds no additional parameter semantics, so the schema carries the full burden; a 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 begins with a specific verb+resource: 'List the Harness Engineering Handbook chapters (HRN-001…)', and expands with a detailed enumeration of the corpus content. It clearly distinguishes from the sibling 'search' tool, stating the appropriate use case for each.

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?

Explicit usage guidance is provided: 'Use this to see the chapter map; use `search` when you have a topic rather than a chapter.' This directly tells the agent when to prefer this tool over the alternative.

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