mcp-android-emulator

assert_screen_contains

Verify that expected text appears on the Android emulator screen during UI tests.

Instructions

Assert that specific text is visible on screen (useful for testing)

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "text": "<text>"
    },
    "name": "assert_screen_contains"
  }
}

Input Schema

Name	Required	Description	Default
`text`	Yes	Text that should be visible
`exact`	No	Exact match (default: false)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv2.0.0Aug 2, 2026

TDQS

C2.8/5.0

Behavior2/5

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

With no annotations, the description carries full responsibility for behavioral disclosure. It does not explain what happens on failure (e.g., error, assertion exception), whether it scrolls or waits, case sensitivity, or how the 'exact' parameter affects behavior. This is a significant gap for an assertion tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness3/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single sentence and front-loaded, but the parenthetical '(useful for testing)' adds little and the wording could be more informative. It is concise but not optimally structured for an agent needing behavioral details.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no output schema and no annotations, the description must convey key behavioral aspects, but it omits failure behavior, exact-match semantics, and any mention of waiting or scrolling. This is incomplete for a tool that executes a test assertion.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description does not add anything beyond the schema; 'specific text' merely echoes the parameter name. No extra meaning is provided for the 'exact' boolean.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's action ('Assert') and target ('specific text is visible on screen'). It distinguishes itself from query tools like get_all_text and get_ui_tree, but does not explicitly contrast with similar assertion or visibility tools (e.g., is_element_visible), so it falls short of a 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides only a vague context ('useful for testing') with no guidance on when to choose this tool over alternatives like wait_for_element or get_all_text. It does not mention under what conditions to use the 'exact' parameter or any exclusions.

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