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

Annotations already mark the tool as read-only, idempotent, and non-destructive. The description adds value beyond that by disclosing what is returned: recorded evidence, derived states with counts and reasons, 'never a score,' and newest-first ordering for capability observations. This gives the agent useful behavioral expectations without contradicting 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 with no filler, front-loading the core action and then grouping behavior by parameter. Every sentence earns its place, and the structure mirrors the tool's two main invocation modes.

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?

Given the rich annotations, an output schema, and schema patterns/enums, the description covers the essential behavior adequately. The main gap is that it never states whether id and capability are mutually exclusive or whether at least one must be supplied, but the mode-based phrasing makes this reasonably inferable.

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 only 33%, so the tool description must compensate. It does explain the two central parameters, id and capability, well. However, it leaves kind and limit semantically unexplained, and the attractor handles rely on their schema descriptions; this partial compensation is adequate but not complete.

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 clear verb and resource: 'Retrieve evidence.' It then specifies two distinct retrieval modes—by id, returning the object plus derived reader states, and by capability, returning observations. This precise scoping distinguishes it from sibling tools like find_capability or find_solutions.

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 clearly explains when to use the id mode versus the capability mode, giving concrete context for each. It does not explicitly name alternative tools or state when not to use this tool, but the within-tool branching is clear enough for an agent to decide how to invoke it.

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