knowl_evidence_list

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

Annotations already declare readOnlyHint=true, so the agent knows it is a safe read operation. The description adds the strategic context but does not disclose other behavioral traits (e.g., output format, ordering, or whether it returns all evidence or a subset). Given the annotations cover the key safety aspect, a 3 is appropriate; the description adds marginal value beyond the purpose.

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 sentences, no fluff. The core function is stated first, followed by a concise use-case rationale. Every word earns its place, and the description is front-loaded with the 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 simple read-only tool with two parameters and no output schema, the description is sufficient. It tells the agent what it does and when to use it. The only missing element is a hint about the output shape, but with no output schema and a straightforward 'list' operation, that is not a critical 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 description coverage is 100%: both 'repo' and 'itemId' have descriptive text. The 'repo' parameter description is unusually detailed, explaining the cross-repo semantics. The tool description does not add any parameter-level information, so it relies on the schema. Baseline 3 is correct.

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 states a specific action ('List the evidence linked to one knowledge item') and clearly identifies the resource. It distinguishes itself from siblings like knowl_recent or knowl_query by focusing on evidence for a single item, and even provides a motivational context (low-confidence, contested, old items).

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 gives explicit when-to-use guidance: 'Use before relying on an item that is low-confidence, contested, or old enough that its support matters more than its claim.' It does not mention alternatives or exclusions, but the scenario is clear enough for an agent to decide when to invoke this tool.

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