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

Goes well beyond the readOnly/non-destructive annotations: it discloses the ranking basis, the fields each result carries (observed price, endpoint liveness, upvotes, how_to_connect), and a genuinely important failure mode — that an empty cheaper_only response may mean a missing/incompatible reference price rather than no alternatives, with the response indicating which. That is exactly the kind of behavioral context annotations cannot express.

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?

Front-loaded with the core purpose and ranking method, and most sentences carry real information. There is mild redundancy — how_to_connect is introduced, then re-enumerated with install/repository and a version tag '(1.10.0)' that reads like changelog noise rather than decision-relevant content.

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 an output schema exists, the description needn't document return values, yet it still summarizes what each alternative carries. Combined with ranking logic, the cheaper_only edge case, alias handling, and cross-tool routing hints, an agent has everything needed to call it correctly and interpret an empty result.

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, but the description adds value by documenting that agent_id accepts aliases (handle, id), which is not in the schema. The cheaper_only caveat also reinforces the parameter's edge-case semantics beyond the schema's own text.

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 (find related alternatives to a known provider) plus the ranking mechanism (text-embedding nearness to the provider's OWN profile, explicitly NOT category lookup). That contrast with category-based discovery distinguishes it from siblings like search_providers and find_market without needing to open their schemas.

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?

Clearly framed as the tool for finding substitutes when you already have a reference provider, and it notes these substitutes are also surfaced inside research_capability and compare_providers, which helps an agent route between overlapping tools. It stops short of an explicit 'use X instead when...' exclusion, so it falls just shy of a 5.

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