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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so no contradiction. Description does not add behavioral details beyond the annotations (e.g., no mention of logging, but schema note covers logging). Credit for adding the 'override any role' capability, but that is more functional than behavioral.

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 sentences, no filler, front-loaded with the main purpose and outcomes. Efficiently communicates the tool's scope and customization feature.

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?

Given a simple 3-parameter tool with 100% schema coverage and an output schema, the description provides sufficient context for invocation. Mentions the compatibility verdict and CSV export, but does not explicitly state prerequisites (e.g., obtaining a valid build_id from list_builds), though that is inferable from siblings.

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 parameters are already documented. Description adds 'Override any role with choices' which clarifies the purpose of 'choices', but this is also implied by the schema ('role → part id overrides'). No significant additional meaning beyond schema.

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?

Description clearly states 'Composes a complete BOM for a reference build' with specific components (quantities, dated prices, rationale, compatibility verdict, CSV export). This is distinct from sibling tools like get_part or search_parts, which focus on individual parts.

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?

Context is clear: use for building a complete BOM for a reference build, with ability to override roles via choices. Does not explicitly mention exclusions or name alternative tools, but the purpose is self-evident and distinct from siblings.

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