build.build_debug_apk

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

With no annotations provided, the description carries the full burden and does disclose important behavioral traits through inline tags: '[approval required][workspace write][network][risk:dangerous]'. It also states the return behavior (returns artifact paths), which goes beyond what the name alone conveys. However, it does not elaborate on what the write entails or why it is dangerous, so it is not a 5.

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 description is a single sentence, front-loaded with risk and permission tags, and efficiently states the action and return value. It is appropriately sized for a simple build tool, though it omits important usage and parameter details that would warrant a 5.

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 the tool has one optional parameter, no output schema, and no annotations, the description adequately covers the primary purpose and return type. However, it lacks context about prerequisites (e.g., needing a project set up), the meaning of the 'kind' parameter, and any error or fallback behavior when no APK is found, so it is not fully 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?

The schema has one optional parameter 'kind' with enum values (flutter, react-native, android) and 0% schema description coverage. The description does not add any meaning about this parameter – it does not explain what each value does, whether the parameter is needed, or what happens if omitted. Since schema coverage is 0%, the description must compensate but fails to do so, leaving the parameter underspecified.

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 ('Build') and resource ('debug APK') and explicitly says it returns discovered APK artifact paths. This clearly distinguishes it from sibling tools like build.build_release_candidate, which builds a release candidate, and ios.build_app, which builds iOS apps.

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 description provides no guidance on when to use this tool versus alternatives such as build.build_release_candidate or build.detect_project. It does not mention preconditions like needing a detected project or when choosing between debug and release builds. The use context is only implied by the tool name and the sibling set, not explicit.

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