This record as markdown: /tools/io-github-kivanccakmak-yaver/eas-build.md
What eas_build does on Yaver
AI agents invoke eas_build to trigger actions in Yaver. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call: builds kicked off, notifications sent, workflows started.
| Parameter | Type | Required | Description |
|---|---|---|---|
platform | string | — | ios or android |
directory | string | — |
Parameters from the server's own tool schema.
Why eas_build is rated High
The tool initiates an Expo Application Services (EAS) build, which compiles and processes application code on remote servers. This is an external operation whose effects depend on the codebase and build configuration arguments. It fits Execute category as it triggers code compilation and infrastructure operations, not just data retrieval.
From the tool's definition Tool performs 'Start an EAS Build' which triggers an external build service operation. Building is a code execution and deployment operation that runs processes on remote infrastructure.
Risk signalsAccepts file system path (directory)
Attacks that exploit this kind of access
The rule that runs eas_build safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Yaver, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For eas_build, this is the rule to start with:
eas_build stays usable, but rate-capped: a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Yaver, apply this rule, and every eas_build call is checked against it from then on.
Questions about eas_build
Start an EAS Build (Expo). It is categorised as a Execute tool in the Yaver MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
eas_build accepts 2 parameters: platform, directory. The full parameter table on this page comes from the server's own tool schema.
Register the Yaver MCP server in PolicyLayer and add a rule for eas_build: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Yaver. Nothing to install.
eas_build is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the eas_build rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for eas_build. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
eas_build is provided by the Yaver MCP server (yaver-cli). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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