Skip to main content
Glama

metro

Prepare the Metro bundler runtime or reload React Native apps on real devices for testing and debugging.

Instructions

Prepare Metro runtime or reload React Native apps.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
cwdNoWorking directory for command execution.
kindNo
portNo
udidNoiOS device UDID selector.
debugNoEnable debug diagnostics.
runIdNoLease run identifier.
actionYes
deviceNoDevice name selector.
serialNoAndroid serial selector.
targetNoAlias for deviceTarget on commands without a UI target field. Interaction commands reserve target for the UI element.
tenantNoRemote tenant identifier.
leaseIdNoExisting lease identifier.
logPathNo
sessionNoAgent-device session name.
platformNoPlatform selector used to resolve a device.
stateDirNoAgent-device state directory.
bundleUrlNo
launchUrlNo
metroHostNo
metroPortNo
timeoutMsNo
listenHostNo
statusHostNo
bearerTokenNo
bridgeScopeNo
includeCostNoInclude per-command agent-cost (cost.wallClockMs, …) in structuredContent. Defaults to off; the default response shape is unchanged.
projectRootNo
deviceTargetNoDevice target form. Maps to the CLI --target flag.
proxyBaseUrlNo
daemonBaseUrlNoRemote daemon base URL.
publicBaseUrlNo
responseLevelNoResponse verbosity: token-cheap digest / default (today) / full. Defaults to default; the default response shape is unchanged.
reuseExistingNo
probeTimeoutMsNo
daemonAuthTokenNoRemote daemon auth token.
iosXctestEnvDirNoWritable directory for iOS XCTest runner env overlays.
mcpOutputFormatNoMCP text content format. Defaults to optimized agent-friendly text; use json for JSON text. Structured content is always returned separately.
runtimeFilePathNo
iosXctestrunFileNoExternally built iOS XCTest runner .xctestrun artifact path.
startupTimeoutMsNo
iosSimulatorDeviceSetNoiOS simulator device-set path used for device resolution.
androidDeviceAllowlistNoAndroid serial allowlist used for device resolution.
iosXctestDerivedDataPathNoDerived data path for external iOS XCTest runner execution.
installDependenciesIfNeededNo
Behavior1/5

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

The description lacks any behavioral disclosure. With no annotations, the description should convey side effects, idempotency, or resource requirements. 'Prepare' and 'reload' imply state changes but are not explained.

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, which is concise but overly brief for a complex tool. It front-loads the action but wastes potential to add value with more detail.

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

Completeness1/5

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

Given 44 parameters and no output schema or annotations, the description is severely incomplete. It fails to explain the two modes, parameter roles, or expected outcome, making it inadequate for correct tool selection and invocation.

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

Parameters2/5

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

Schema description coverage is low (52%) and the description adds no parameter meaning. Many parameters (e.g., 'kind', 'port', 'bundleUrl') have no description in schema or description field, leaving agents uninformed on usage.

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 states the tool prepares Metro runtime or reloads React Native apps, which clearly identifies the tool's domain. However, it does not distinguish between 'prepare' and 'reload' beyond name, nor differentiate from sibling 'react-native' tool.

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?

No guidance is provided on when to use this tool versus alternatives. The description does not mention prerequisites, when to prefer 'prepare' over 'reload', or compare to siblings like 'react-native'.

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

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/callstack/agent-device'

If you have feedback or need assistance with the MCP directory API, please join our Discord server