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

Annotations already declare destructiveHint=true and idempotentHint=true, but the description adds the crucial specificity of what is destroyed: the current quantity is replaced, not incremented. It does not cover auth/permission requirements or whether the memo is written to stock history, which keeps it just short of 5.

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?

Three terse clauses, front-loaded with the WRITE marker and the absolute-vs-relative distinction before the endpoint. No filler sentences.

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 4-parameter mutation with full schema coverage, annotations covering the safety profile, and no output schema to explain, the description carries what matters. The only real gap is the unmentioned optional memo parameter and any permission prerequisites.

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 genuine meaning the schema lacks: stock_amount is an absolute level that overwrites, not a delta — the schema only says 'The new quantity.' It also frames product_id/store_id as a single product in a single store pairing.

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 — set the absolute stock quantity of one product in one store — and adds the PATCH endpoint. It explicitly distinguishes itself from the sibling smaregi_adjust_stock, so an agent can route without opening either schema.

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?

Names the alternative (smaregi_adjust_stock) and the exact condition that selects it (relative change vs. absolute set). That is an explicit when-to-use-which rule, not an implied one.

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