Update stock quantities

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

Annotations already flag write/non-idempotent behavior, and the description adds concrete details not present in annotations: exact POST endpoints, per-request item cap of 1000, undocumented response body returned verbatim with 2xx meaning success, and a recommendation to verify via query_stocks. No contradictions with annotations.

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 three sentences with the main action front-loaded. Every sentence adds essential operational detail—mode behavior, endpoints, limits, response handling, and verification—without any filler or 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 write tool with no output schema, the description covers the essential operational facets: two modes, per-store scope, response passthrough, success condition, and follow-up verification. It could also address error handling or auth, but given annotations and sibling context, it is sufficiently complete.

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 baseline is 3, but the description adds value by explaining the default for 'mode' and mapping each mode to its endpoint and intended use case. It also reinforces the 1000-item limit already in the schema, providing marginal additional meaning.

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 opens with 'Writes stock quantities for one store,' a specific verb+resource that clearly differentiates it from read tools like query_stocks. It further distinguishes the two modes (modify vs initialize) with distinct endpoints, making the tool's purpose unambiguous.

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 mode selection guidance: modify (default) for regular updates and initialize for first-time stock load. It also directs the agent to verify results with query_stocks, indicating the appropriate companion tool. However, it does not explicitly state when not to use this tool versus other alternatives.

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