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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint false, so the safety profile is covered. The description adds substantial behavioral context beyond annotations: tests run in order with no branching or early exit, the verdict mapping is fully mechanical (all passing => SUPPORTED, zero passing => REFUTED, otherwise PARTIALLY SUPPORTED), and the tool is not an open-ended research agent. This goes well beyond what annotations provide.

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 compact and well-organized: first sentence defines the action, second covers typical use cases, third imposes constraints, fourth explains the verdict algorithm, fifth names alternatives. Every sentence earns its place, and there is no redundant or filler content. It is appropriately sized for a tool of this complexity.

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 tool's moderate-to-high complexity (multiple test types, ordered execution, verdict logic), the description covers all key aspects: what it does, when to use it, behavioral constraints, verdict determination, and sibling alternatives. An output schema exists for return values, and the description already explains the verdict mapping, so nothing critical is missing.

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%, so the baseline is 3. The description adds some context by listing example check types (endpoint reachability, npm search counts, substring presence) and emphasizing that tests must be explicitly defined, but this largely restates information already in the schema. The hypothesis parameter is self-explanatory. No additional syntax or format details beyond the schema are provided, so a 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?

The description clearly states the tool 'Run a small verification plan made of concrete live checks and summarize whether a hypothesis is supported' with a specific verb and resource. It also distinguishes itself from siblings by explicitly naming alternatives (verify_claim, estimate_market, compare_competitors) and framing itself as a coordination tool, not an open-ended research agent.

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 provides explicit when-to-use guidance ('Use this when one conclusion depends on multiple simple checks...') and when-not-to-use guidance with named alternatives ('Use verify_claim when you already have evidence URLs...'). It also restricts usage by stating 'every test must be explicitly defined in advance' and 'no branching or early exit', which clarifies the boundary versus more flexible research tools.

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