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

Beyond the annotations (readOnlyHint=false, destructiveHint=true, openWorldHint=false) it discloses that execution is asynchronous, that manually typed merchant values are never overwritten, and that AI fields draw down a monthly allowance that can halt the work. Those are exactly the behavioral facts an agent needs and none are derivable from the structured fields.

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?

A single dense passage that front-loads the core action and execution mode before the scope definitions and constraints. Every clause carries distinct information — no repetition of the name or title, no filler.

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?

Return values need not be explained since an output schema exists, and the description covers the important operational risks: background execution, preservation of manual values, and quota exhaustion. It does not say how to observe progress or results of a background run, or whether repeat calls are idempotent, which is a minor gap for an async mutation.

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% and the scope enum already documents both values, so the description's scope gloss largely restates the schema, though 'ones that failed' adds a small amount of clarity about the 'stale' bucket. fieldId semantics are left entirely to the schema's 'as list_smart_fields returned it' note. 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?

States a specific verb and resource ('Compute a smart field's values') plus the execution mode ('in the background'), and immediately defines the two modes it operates on. It is clearly distinguishable from siblings like create_smart_field and list_smart_fields, which define or enumerate fields rather than compute values.

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 gives the decision rule for choosing between 'missing' and 'stale' by explaining what each scope covers, which is real when-to-use guidance. It stops short of stating prerequisites (e.g. that the field must already exist via create_smart_field) or when not to call it.

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