Record a price by hand

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

Discloses the important side effect (creates a watch for the URL if not present) and the return value (stored price and observation count). No annotations are present, so the description carries the full burden and meets it well.

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 succinct sentences that front-load the purpose and then cover side effects and return value. Every word earns its place with no 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 tool with no output schema, the description helpfully mentions the return contents (stored price and observation count) and side effects. It could specify the response shape more precisely, but it is sufficient for typical use.

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 descriptions already cover all four parameters, including format examples for price and ISO for currency. The description does not add significant extra semantic meaning beyond what the schema provides, so 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?

Clearly states the action (store a price), the resource (a manually read price), and the specific context (shops that block automated requests). It is easily distinguished from sibling tools like price_check, which imply automated retrieval.

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?

Explicitly indicates when to use this tool: when you read the price yourself and automated requests are blocked. This provides clear guidance relative to automated price-checking alternatives.

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