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

Beyond the annotations (which only declare it is a non-idempotent, non-destructive write), the description discloses the key behavioral effect: the accord is a virtual material carrying the flattened composition so IFRA, allergens, cost, and scent profile can see inside it, placed at the accord's own aromatic strength. It omits reversibility and auth/permission requirements, but the semantic payoff is substantial.

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 trigger condition is front-loaded ('Use this when...') and the single dense sentence earns its clauses by explaining the accord's virtual-material behavior. The trailing 'Optionally at an amount in grams' is a slightly awkward fragment but carries real information.

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 three-parameter mutation tool with no output schema, the description conveys what the operation produces and why it matters (downstream IFRA/allergen/cost/profile visibility). It lacks guidance on failure modes, duplicate handling, or whether the source formula must already exist, but it is otherwise complete enough to invoke 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 coverage is 67%; 'source' and 'formula' are documented in the schema, while 'grams' has no schema description. The description only notes the amount is optional and in grams, adding little syntax or default detail, so it does not fully compensate for the undocumented parameter. A 3 is the appropriate baseline.

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 and resource: using a saved formula as a single ingredient inside another, mirroring the app's native accords. It is far more than a restatement of the title, though it does not explicitly name or differentiate itself from close siblings like decompose_accord, view_accord, or resync_accord.

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?

It gives clear triggering context ('Use this when the user wants to use one of their saved formulas as a single ingredient inside another'), which tells the agent exactly when to reach for this tool. It stops short of naming alternatives or exclusions, so the agent must infer that decompose_accord is the inverse operation.

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