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

Adds materially beyond the annotations by disclosing the required Pricewatcha API key format and where to obtain it, and by describing the structured error object (error.code, error.message, error.http_status, error.retry_recommended, error.retry_after_seconds). The retry fields give an agent actionable recovery behavior that the openWorldHint/idempotentHint annotations alone would not convey.

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 purpose, then constraint, then auth, then error shape — every sentence carries operational information. The final error sentence is long but justified for a tool whose failure modes the agent must handle.

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?

An output schema exists so return values need no prose, and the description still covers the two things it must: credential prerequisites and the failure contract. With 9 parameters, 2 required, and full schema coverage, nothing an agent needs to call this correctly 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 coverage is 100%, so the baseline is 3, but the description supplies a genuine cross-parameter rule the schema cannot express: at least one of notify_on_drop, notify_on_rise, min_threshold_price, or max_threshold_price must be provided. It also clarifies the intent split between boolean flags and numeric thresholds.

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 ("Create a price alert for a product") that an agent can immediately distinguish from list/get/update/delete siblings. It does not explicitly name update_price_alert as the alternative for modifying an existing alert, so it falls just short of full sibling differentiation.

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?

Gives clear in-tool guidance on how to configure the alert: threshold-free booleans versus numeric target prices, plus the hard constraint that at least one of the four must be set. It does not address when to prefer this over update_price_alert or track_product, so there is no explicit exclusion or alternative routing.

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