> ## Documentation Index
> Fetch the complete documentation index at: https://executioncontrolprotocol.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Why ECP

> Why ECP (Execution Control Protocol) exists: a portable execution layer for AI agents on top of MCP.

# Why ECP

ECP (Execution Control Protocol) fills the **execution layer** between tool calling and production agent systems.

| Layer     | Standard      |
| --------- | ------------- |
| Models    | Provider APIs |
| Tools     | MCP           |
| Agents    | Frameworks    |
| Execution | **ECP**       |

If MCP standardizes how AI systems **call tools**, ECP standardizes how AI systems **run**: portable workflows, governed environments, policies, and host runtimes.

## The problem

As agents move from prototypes to production:

* Tool permissions become unclear
* Actions are hard to audit
* Context and mounts are inconsistent
* Execution environments are not reproducible
* Governance is bolted on after the fact

Teams solve this with one-off orchestration code. There is no shared way to package “how this agent runs here.”

## What ECP gives you

* **Workflows** — versioned, portable graphs (Fluent/TS or JSON)
* **Environments** — runtime + extensions + policies that bind a host
* **Deterministic ops** — validate, describe, search, encode, decode, patch, run
* **Hosts** — Node CLI, browser runtime, MCP adapter
* **Composability** — same operational APIs after `env.init()`, regardless of host

ECP is not another agent framework or chat UI. It is infrastructure for governed execution.

## Next steps

* [Core concepts](/learn/concepts)
* [Relationship to MCP](/learn/relationship-to-mcp)
* [Quickstart](/getting-started/quickstart)