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

Annotations only supply destructiveHint=true; the description goes further by stressing that it modifies live store data, explaining the delta direction, and disclosing the return shape {updateCount, warning?}. That return detail is especially valuable since no output schema exists.

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 the action and its destructive nature, then semantics, then the API mapping. Dense and nearly waste-free, though the REST endpoint/body detail is marginal for an agent choosing a tool.

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 simple 2-parameter mutation with only destructiveHint available, the description covers effect, direction, and return value. Nothing essential for correct invocation is missing, though permission/rate-limit context is absent.

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 description coverage is 100%, so both parameters are already documented by the schema, and the description largely restates the delta convention. Baseline 3 applies since the schema carries the semantics.

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 (adjusts), resource (product in-stock quantity), and the mechanism (by a delta). This is clearly distinguishable from the get/list/search/update siblings, and the delta semantics are immediately understandable.

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?

Usage is implied by 'this MODIFIES live store data' and the positive/negative delta convention, which tells the agent when the tool applies. However, no alternative is named (e.g. setting absolute stock) and no prerequisites, auth, or when-not guidance is given.

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