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

Annotations already cover the safety profile (readOnlyHint=true, openWorldHint=false), and the description adds meaningful behavior beyond that: only edges at confidence >= 0.7 with verbatim source evidence are published, so results are filtered and checkable. It also discloses the billing plan and per-call price, though it does not cover pagination or result limits.

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 core purpose is front-loaded and the filter semantics follow logically. The ALL-CAPS emphasis and the inline pricing block duplicate the apis://prices pointer, adding mild noise, but the overall structure remains readable and mostly earns its space.

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?

With no output schema, the description carries the return-value burden and does so by enumerating the edge fields (provider, tag, OpenAPI file, confidence, quoted fragment). It covers filtering and pricing; only pagination/volume behavior is unaddressed, a minor gap for a simple read tool.

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 two parameters (capability slug/BC id, and the optional 'context' rationale) are already documented in the schema. The description adds no parameter-level syntax or format guidance, so the 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?

States a specific verb and resource ('get capability edges') and defines what an edge is in concrete terms: provider, tag, OpenAPI file, calibrated confidence, and a quoted contract fragment. It clearly distinguishes this evidence-layer tool from a plain capability lookup, though it never names the sibling tools (get_capability, get_provider_evidence) it should be preferred over.

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?

Provides an implied use case — 'this is what you cite when someone asks "says who?"' — which gives an agent a sense of when to reach for it. It stops short of explicit when-to-use/when-not or naming an alternative, so the routing decision is left partly to inference.

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