postfader_validate_run

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true. The description adds the specific guarantee 'without changing FL', reinforcing the non-destructive nature. It also mentions validating 'current capabilities', which is a useful behavioral detail not in the annotations. This adds value beyond what the annotations provide.

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 a single, concise sentence with no redundancy. It front-loads the key action ('Validate') and the critical constraint ('without changing FL'). Every word earns its place, and the structure is immediately scannable.

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?

The tool takes two complex nested objects and has an output schema, so the return format is covered elsewhere. The description clearly states the non-mutating nature and the validation scope. It could mention what happens on validation failure (e.g., whether it returns blockers), but given the output schema, the description is adequate for an agent to invoke it correctly.

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 (request and plan) are well documented in the input schema. The description itself adds no additional parameter-level detail beyond what's in the schema. With high schema coverage, a baseline of 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?

The description states a specific verb ('Validate'), a specific resource ('a bounded Production Run and current capabilities'), and explicitly notes the non-mutating nature ('without changing FL'). This clearly distinguishes it from sibling tools like postfader_execute_run or postfader_continue_run, which are execution-oriented. An agent can immediately understand the tool's purpose.

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 clearly implies a pre-execution validation step by emphasizing 'without changing FL' and 'current capabilities'. While it doesn't explicitly name alternatives like postfader_execute_run, the context strongly suggests this is a read-only pre-flight check. It could be improved by explicitly stating 'use before postfader_execute_run', but the intent is clear.

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