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

Annotations already declare readOnlyHint=true, so the read-only nature is covered. The description adds valuable context by specifying 'directly supporting', indicating only immediate sub-claims are returned (not transitive), and notes the node id must come from a prior recall. This goes beyond the annotations without contradiction.

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: the first states the core purpose, the second gives the usage hint. It is front-loaded, with no redundant words or unnecessary detail.

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 read-only tool with two parameters and no output schema, the description adequately covers what it does, how to call it, and where to obtain the required input. It does not describe the exact return format, but given the straightforward nature and lack of schema, this is a minor gap.

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%, so the baseline is 3. The description adds meaning by explaining that node_id originates from a prior recall, which is not in the schema. The workspace parameter is already self-explanatory, so no extra description 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?

The description uses a specific verb ('Return') and a precise resource ('sub-claims directly supporting a given claim'), making the tool's function unambiguous. It also distinguishes from siblings like recall (which likely retrieves claims) and evidence (which may show supporting evidence) by focusing on direct sub-claims.

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?

It provides clear context by instructing to pass a node id 'returned by a prior recall', which tells the agent when to use it. However, it does not explicitly mention alternatives or when not to use it, though the dependency on recall is a strong implicit guideline.

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