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Mock Harness reference

The mock harness replaces the real CLI spawn with a scripted event stream. Use it for tests, CI, and demos where real credentials or network access are undesirable.

Pagewiki/docs/agent-mux/tutorials/mock-harness.mdOutgoing · 0Incoming · 1

Mock Harness

The mock harness replaces the real CLI spawn with a scripted event stream. Use it for tests, CI, and demos where real credentials or network access are undesirable.

Enabling

Two equivalent switches:

bash

amux run claude --use-mock-harness --prompt "test"

or globally:

bash

export USE_MOCK_HARNESS=1
amux run claude --prompt "test"

Programmatically:

await client.run({
  agent: 'claude',
  prompt: 'test',
  useMockHarness: true,
});

Scenarios

The mock emits a deterministic sequence of AgentEvents chosen by scenario name:

Scenario	What it emits
`text`	A few `text_delta` events and a final `done`.
`tool-call`	`text_delta` → `tool_call_start` → `tool_call_result` → `done`.
`thinking`	`thinking_delta` events before the final message.
`error`	Emits an `error` event with `recoverable: false`.
`session-resume`	Replays a prior session snapshot.

Pick one with --scenario:

bash

amux run claude --use-mock-harness --scenario tool-call --prompt "x"

If you invoke the package binary directly, the same agent scoping is available there too:

bash

mock-harness --agent claude --list
mock-harness --agent claude --scenario tool-call

Interactive approval scenarios under packages/agent-mux/harness-mock now model real gating semantics rather than timer-only replay:

interactive:yolo auto-approves and then emits the post-approval output.
interactive:prompt waits for stdin before it emits the post-approval output and exits.
interactive:deny auto-denies, emits the denial path, and exits non-zero.
interactive:timeout waits for approval until the configured timeout, emits a timeout error, and exits non-zero.

Why use it

**CI**: No API keys, no flakiness.
**Adapter tests**: Validate parseEvent without invoking the real CLI.
**Integration tests**: Exercise hooks, session-save paths, and the event stream in isolation.

See Harness & Mock for the full event script format.

Mock Harness reference

The mock harness replaces the real CLI spawn with a scripted event stream. Use it for tests, CI, and demos where real credentials or network access are undesirable.

Pagewiki/docs/agent-mux/tutorials/mock-harness.mdOutgoing · 0Incoming · 1

Mock Harness

The mock harness replaces the real CLI spawn with a scripted event stream. Use it for tests, CI, and demos where real credentials or network access are undesirable.

Enabling

Two equivalent switches:

bash

amux run claude --use-mock-harness --prompt "test"

or globally:

bash

export USE_MOCK_HARNESS=1
amux run claude --prompt "test"

Programmatically:

await client.run({
  agent: 'claude',
  prompt: 'test',
  useMockHarness: true,
});

Scenarios

The mock emits a deterministic sequence of AgentEvents chosen by scenario name:

Scenario	What it emits
`text`	A few `text_delta` events and a final `done`.
`tool-call`	`text_delta` → `tool_call_start` → `tool_call_result` → `done`.
`thinking`	`thinking_delta` events before the final message.
`error`	Emits an `error` event with `recoverable: false`.
`session-resume`	Replays a prior session snapshot.

Pick one with --scenario:

bash

amux run claude --use-mock-harness --scenario tool-call --prompt "x"

If you invoke the package binary directly, the same agent scoping is available there too:

bash

mock-harness --agent claude --list
mock-harness --agent claude --scenario tool-call

Interactive approval scenarios under packages/agent-mux/harness-mock now model real gating semantics rather than timer-only replay:

interactive:yolo auto-approves and then emits the post-approval output.
interactive:prompt waits for stdin before it emits the post-approval output and exits.
interactive:deny auto-denies, emits the denial path, and exits non-zero.
interactive:timeout waits for approval until the configured timeout, emits a timeout error, and exits non-zero.

Why use it

**CI**: No API keys, no flakiness.
**Adapter tests**: Validate parseEvent without invoking the real CLI.
**Integration tests**: Exercise hooks, session-save paths, and the event stream in isolation.

See Harness & Mock for the full event script format.