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

With no annotations, the description carries the full burden and does disclose useful traits: a permission requirement and that the actual cost counts toward both daily caps (a rate/limit behavior). It omits whether the build is reversible, what error results from a locked blueprint or exhausted cap, and what requestId does beyond being a UUID.

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?

Three short sentences, front-loaded with the core action and followed by the constraint. Slight waste in restating the UUID requirement already encoded in the schema, but nothing else is padded.

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 mutation tool with no annotations and no output schema, the description covers permission and cost-cap behavior but leaves the return value (the new invention) and the main failure modes unstated. Adequate to call correctly, 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 0%, so the description must do the work. It identifies blueprintId as the blueprint to build and flags requestId as a required UUID, but the UUID format is already in the schema and it never explains that requestId is an idempotency/dedup key, which is the main thing an agent needs to know.

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: 'Build one unlocked blueprint using blueprintId'. The 'unlocked' qualifier and 'one' scope distinguish it from dismantle_invention, gift_invention, and blueprint_list without needing to open schemas. It stops short of naming a sibling explicitly, so it is clear but not maximally differentiating.

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?

'Requires play permission' is a genuine precondition that helps an agent decide whether it can call the tool. However, there is no guidance on when to choose this over dismantle_invention or gift_invention, nor any exclusion such as what happens if the blueprint is locked or funds are insufficient.

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