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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description correctly reflects a non-mutating scan. It adds the core behavioral detail—triangulating three price sources to compute signals—which is beyond annotations. However, it does not mention data freshness, staleness, or the fact that includeLive requires an API key (that is left to the schema). For a read-only tool, the description adds moderate context but not rich operational caveats.

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 tightly written sentences, with the core purpose and key signals front-loaded. The bilingual repetition is intentional and adds no fluff. Every word earns its place, and there is zero redundancy.

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 read-only scanner with full parameter descriptions and an output schema, the description covers the central function and signal categories. The main gap is the lack of usage guidance relative to siblings, and it doesn't touch on operational constraints like data licensing or API-key requirements (though those are hinted in the includeLive parameter schema). Overall it is adequate but not exhaustive for a tool with 5 parameters and many siblings.

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 every parameter is already documented in the input schema. The description adds value by mapping signal types (discount, inheritance_edge, overheated) to the tool's purpose, which clarifies the meaning of signalType. However, it doesn't elaborate on output_mode or limit beyond what the schema provides, so the added value over the schema is modest.

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 verb and resource: 'Price triangulation arbitrage scanner' that cross-checks three named data sources (rosenka, koji, tx) and produces three concrete signal types. This clearly distinguishes it from sibling tools like discover_opportunities or composite_value_score, which target different analytical angles.

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 explains what the tool does but never states when to prefer it over alternatives, nor does it give exclusions or conditions. Sibling tools like discover_opportunities or cross_analyze_real_estate_market overlap in domain, yet no routing guidance is provided. An agent would have to infer usage from the tool name alone.

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