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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds that output includes 'dated indicative prices' and 'per-line rationale', which hints the pricing is non-binding, but with an output schema present most of the return-shape detail is redundant and no logging/persistence or performance behavior is disclosed.

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 written sentences, front-loaded with the action and resource, with the override capability in a short trailing sentence. The output enumeration is slightly list-heavy and partly duplicates the output schema, but nothing is wasteful.

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?

With an output schema present the description need not explain return values, and annotations cover the safety profile. The remaining burden — what the tool produces at a high level, that build_id selects a known reference build, and that choices are per-role overrides — is all covered.

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 all three parameters (including the nested 'choices' map) are already documented in the schema; baseline is 3. The description's 'Override any role with choices' adds the useful nuance that choices are overrides layered on an existing build, but no role vocabulary or error behavior for unknown roles.

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 ('Composes a complete BOM for a reference build') and enumerates the concrete outputs it produces, so the agent knows it is a generative build tool rather than a reader. It does not, however, name or contrast itself with the obvious siblings view_bom or check_compatibility, leaving the boundary to inference.

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 only usage guidance is 'Override any role with choices', which describes a capability rather than a when-to-use condition. Nothing tells the agent when to call build_bom instead of view_bom (reading an existing BOM) or check_compatibility, nor whether build_id must already exist.

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