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alpineagents

Testing

TGoddessana/alpineagents

Testing¶

Test an agent without an API key or network. FakeModel replaces the model and returns prepared replies in order.

A test¶

from pathlib import Path

from alpineagents import Agent, State, tool
from alpineagents.testing import FakeModel, tool_call


@tool
def read_file(path: str) -> str:
    """Read a file"""
    return Path(path).read_text()


agent = Agent(model="claude-sonnet-5", tools=[read_file])


def test_reads_the_file_then_answers(tmp_path, monkeypatch):
    monkeypatch.chdir(tmp_path)
    Path("main.py").write_text("x = 1 +\n")
    fake = FakeModel([
        tool_call("read_file", path="main.py"),
        "Line 1 has a syntax error",
    ])
    state = State("Find the bug in main.py")

    agent.copy(model=fake, reporter=None).run(state)

    assert state.answer == "Line 1 has a syntax error"
    assert state.stopped_by == "is_answered"
    assert fake.remaining == 0

FakeModel gets two replies: a call to read_file, then the answer.
agent.copy(model=fake, reporter=None) is a new Agent with the same settings, except the fake model and no terminal output.
The assertions check the answer, why the run stopped, and that every reply was used.

Replies FakeModel accepts¶

Each model request takes the next item: every think, every ask attempt and every compact (also from compact_if_full). When the items run out, the request raises RuntimeError.

Item	The reply
`"text"`	A text reply without tool calls
`tool_call("name", arg=value)`	A reply with one tool call
A list of text and tool calls	A reply with those parts in order, for example `["Let me check.", tool_call(...)]`
An exception instance, such as `RateLimitError("slow down")`	The request raises it
A `Reply` object	Used as is
A function that takes the `Request`	Its return value, read by the rules above

fake.requests holds every request the model received. Use it to check what the model saw:

assert [t.name for t in fake.requests[0].tools] == ["read_file"]

Questions to the person¶

FakeHuman answers ask_human with prepared answers in order. agent is the Agent from Ask before a tool runs:

from alpineagents.testing import FakeHuman, FakeModel, tool_call

fake = FakeModel([tool_call("write_file", path="a.md", content="x"), "Skipped"])
human = FakeHuman(["no"])
agent.copy(model=fake, human=human, reporter=None).run("Write a.md")
assert human.remaining == 0

An answer that does not fit the question's returns type is skipped, and the next one is used.

What to assert¶

To check	Assert on
The result	`state.answer`
Why the run stopped	`state.stopped_by`
How many turns	`state.turn`
What happened, in order	`state.history`, for example `[h.kind for h in state.history]`. The kinds are listed in the Data types API
What the model saw	`fake.requests`

Testing API