set_mass_trait_property

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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the mutation profile is covered structurally. The description adds useful mechanism context (values are parsed via FProperty::ImportText_Direct reflection) and enumerates the response keys, including a 'saved' flag that hints at a disk write side effect, but it never says what happens on parse failure or whether the overwritten value is recoverable.

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 compact fragments, zero filler: the action is front-loaded and the return shape is appended as a single terse line. Nothing repeats the tool name or the annotations.

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 four-parameter mutation tool this is close to sufficient: annotations carry the safety profile, the schema documents every parameter, and the description supplies the return keys in lieu of an output schema. The remaining gap is failure behavior (trait missing, unparseable value, save failure), which an agent must guess.

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 the schema already explains all four parameters, including dotted paths and the ImportText string parsing. The description's restatement of 'name or dotted path' and the value semantics adds only marginal value, which lands at the 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?

States a precise verb+resource ('Set a property ... on a trait in a Mass config') plus the mechanism (reflection / ImportText), which cleanly distinguishes it from the read-side sibling get_mass_trait_property. An agent can tell what will change without opening any schema.

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?

No when-to-use guidance, no statement of preconditions, and no routing to alternatives (e.g., add_mass_trait for traits not yet present, or get_mass_trait_property to read first). The only prerequisite, that the trait must already exist, lives in the schema's trait_class description rather than here.

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