android_assert

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

With no annotations provided, the description carries the transparency burden. It discloses the key behavioral trait—the screenshot is sent to LM Studio rather than returned into context—and specifies the return contract of PASS or FAIL. It does not mention failure modes or prerequisites like LM Studio availability, but the most surprising behavior is well covered.

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 compact and front-loaded: the first sentence states the core purpose, the second adds the cost/behavior context, and the Args list is terse. No redundant or filler text is present.

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 3-parameter tool with no output schema and no annotations, the description covers purpose, return values, and argument defaults. Minor gaps remain around error handling and the local VLM configuration prerequisite, but the essential information for a normal call is present.

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 0%, so the Args section is the only source of meaning. It clarifies question as a yes/no claim with an example, states device as a serial defaulting to the first physical device, and identifies model as an LM Studio model id defaulting to the configured one. This strongly compensates for the bare 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?

The description opens with a specific verb+resource: 'Check a claim about the current screen using the local VLM' and states the concrete outcome 'Returns PASS or FAIL'. This clearly differentiates it from capture/dump siblings like android_screenshot and android_ui_dump by focusing on assertion rather than raw output.

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 'cheap oracle' framing and the statement that 'the screenshot goes to LM Studio, not into your context' give clear context for when to use this tool: cheap screen verification without polluting the conversation. It does not explicitly list exclusions or name alternatives, so it stops short of full when-not-to-use guidance.

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