Android Testing Guide

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

Annotations declare readOnlyHint=true, which the description aligns with by presenting the tool as a reference. The description adds value by detailing the topics covered (e.g., unit tests, compose testing, espresso, hilt testing) and implying the tool returns information based on the optional topic parameter.

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 dense with information but slightly redundant (list appears twice). It is front-loaded with the core purpose and topics, making it efficient for an agent to parse.

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 simple reference tool with one optional parameter and no output schema, the description adequately explains functionality, topics, and calling context. It could specify the return format (e.g., text or markdown) but is otherwise 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 input schema covers 100% of parameters and includes a description for 'topic'. The description adds extra guidance: 'Leave empty to list all.' This enhances usability beyond the schema alone.

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 clearly states it is a 'Complete Android testing reference' and lists specific topics (unit tests, Compose UI, Espresso, etc.), with an explicit call to action: 'Call before writing any test.' This distinguishes it from sibling tools, which are other Android guides (e.g., large_screen_guide, navigation3_guide) not focused on testing.

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 includes when to use the tool ('Call before writing any test'), providing clear context. However, it does not explicitly mention when not to use it or alternative tools, though no direct testing alternative exists among siblings.

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