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

The description reveals a non-obvious side effect beyond the annotations: editing one copy of a stack of N splits the stack, which explains why destructiveHint=true matters here. It also discloses the confirm gating condition, adding genuine behavioral context the annotations do not carry; it stops short of saying whether edits are reversible.

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?

Two tightly packed sentences with the key constraint front-loaded; almost no wasted words. The phrase 'Always scope:one' is internal jargon that slightly obscures an otherwise clear statement.

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 destructive mutation tool with no output schema and 7 parameters at 29% coverage, the definition covers the critical gating and side effects but leaves the grading parameter trio and the effect on existing values under-specified. Adequate, not 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 only 29%, so the description should compensate more than it does. It explains the semantics of 'confirm' (required when quantity > 1) and maps to price/condition/grade, but leaves 'grader' versus 'gradeValue' versus 'gradeLabel' relationships unexplained beyond the schema's own note.

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 ('Edit ONE copy') and enumerates the editable attributes (purchase price, condition, grade). The emphasis on ONE copy implicitly separates it from stack-level or sealed-product siblings like update_sealed, though no sibling is named explicitly.

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?

Gives a conditional rule ('confirm=true is required when quantity > 1') and warns that a stack of N is split, which is real usage guidance. However, it never points to an alternative tool (e.g., remove_copy for deletion or update_sealed for sealed items), so routing guidance is only partial.

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