unsloth/studio/backend/tests/test_safetensors_tool_loop.py
Daniel Han 8848a310df
Studio: clean-room compact RAG (knowledge bases, hybrid search, fast indexing) (#5910)
Adds a self-contained RAG stack to Studio: knowledge bases with chunked indexing, hybrid (dense + lexical) retrieval, and an automatic first-pass context inject into chat. Embeddings run through a local llama-server GGUF backend (default unsloth/bge-small-en-v1.5-GGUF) with a sentence-transformers fallback. The chat tool loop gains a search_knowledge_base tool, a per-turn re-search cap, and source citation, layered on top of the shared ToolLoopController.
2026-06-09 21:17:04 -07:00

1183 lines
45 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0
"""Tests for the safetensors agentic tool loop.
Covers the ``tool_call_parser`` helpers and the cumulative-text state machine in
``run_safetensors_tool_loop``, run against fake single-turn generators (no model
load). Edge cases: plain answers, JSON and XML tool-call forms, truncated/unclosed
calls, tool-result feedback, bad-JSON heal, duplicate-call short-circuit,
``__IMAGES__`` sentinel stripping, executor errors, cancel, and the iteration cap.
"""
import threading
from typing import cast
import pytest
from core.inference import safetensors_agentic
from core.inference.safetensors_agentic import (
_coerce_arguments,
_detect_render_html_tool_start,
run_safetensors_tool_loop,
strip_tool_markup_streaming,
)
from core.inference.tool_call_parser import (
RAG_MAX_SEARCHES_PER_TURN,
has_tool_signal,
parse_tool_calls_from_text,
strip_tool_markup,
)
from utils.datasets import is_gpt_oss_model_name
# ────────────────────────────────────────────────────────────────────
# parse_tool_calls_from_text
# ────────────────────────────────────────────────────────────────────
class TestParser:
def test_json_tool_call(self):
text = '<tool_call>{"name":"web_search","arguments":{"query":"hello"}}</tool_call>'
result = parse_tool_calls_from_text(text)
assert len(result) == 1
tc = result[0]
assert tc["type"] == "function"
assert tc["function"]["name"] == "web_search"
# Arguments must always be a JSON string.
assert isinstance(tc["function"]["arguments"], str)
assert "hello" in tc["function"]["arguments"]
def test_json_tool_call_unclosed(self):
# No </tool_call>; balanced-brace extractor must still close it.
text = '<tool_call>{"name":"python","arguments":{"code":"print(1)"}}'
result = parse_tool_calls_from_text(text)
assert len(result) == 1
assert result[0]["function"]["name"] == "python"
def test_json_tool_call_unclosed_requires_healing(self):
text = '<tool_call>{"name":"python","arguments":{"code":"print(1)"}}'
assert parse_tool_calls_from_text(text)[0]["function"]["name"] == "python"
assert parse_tool_calls_from_text(text, allow_incomplete = False) == []
def test_xml_function_call(self):
text = "<function=python><parameter=code>print('hi')</parameter></function>"
result = parse_tool_calls_from_text(text)
assert len(result) == 1
assert result[0]["function"]["name"] == "python"
assert "print('hi')" in result[0]["function"]["arguments"]
def test_xml_unclosed(self):
# Closing tags omitted; parser must still extract the value.
text = "<function=terminal><parameter=command>ls -la"
result = parse_tool_calls_from_text(text)
assert len(result) == 1
assert result[0]["function"]["name"] == "terminal"
assert "ls -la" in result[0]["function"]["arguments"]
def test_xml_unclosed_requires_healing(self):
text = "<function=terminal><parameter=command>ls -la"
assert parse_tool_calls_from_text(text)[0]["function"]["name"] == "terminal"
assert parse_tool_calls_from_text(text, allow_incomplete = False) == []
def test_code_with_embedded_xml(self):
# A code parameter with a literal </parameter> must not truncate: the
# parser uses end-of-body as the only boundary for single-param calls.
text = (
"<function=python><parameter=code>html = '<a></a>'\n"
"print('hi')</parameter></function>"
)
result = parse_tool_calls_from_text(text)
assert len(result) == 1
assert "print('hi')" in result[0]["function"]["arguments"]
def test_function_signal_inside_parameter_is_literal(self):
text = (
"<function=python>"
"<parameter=code>print('<function=render_html>')</parameter>"
"</function>"
)
result = parse_tool_calls_from_text(text)
assert len(result) == 1
assert result[0]["function"]["name"] == "python"
assert "<function=render_html>" in result[0]["function"]["arguments"]
def test_multiple_calls(self):
text = (
'<tool_call>{"name":"web_search","arguments":{"query":"a"}}</tool_call>'
'<tool_call>{"name":"web_search","arguments":{"query":"b"}}</tool_call>'
)
result = parse_tool_calls_from_text(text)
assert len(result) == 2
assert result[0]["function"]["name"] == "web_search"
assert result[1]["function"]["name"] == "web_search"
def test_bad_json_does_not_raise(self):
text = "<tool_call>{not valid json}</tool_call>"
result = parse_tool_calls_from_text(text)
# Bad JSON is dropped silently; caller can fall back to text.
assert result == []
def test_has_tool_signal(self):
assert has_tool_signal("blah <tool_call> x")
assert has_tool_signal("hi <function=foo>...")
assert not has_tool_signal("hello world")
def test_render_html_start_detector_uses_first_tool(self):
assert _detect_render_html_tool_start("<function=render_html>")
assert _detect_render_html_tool_start(
'<tool_call>{"name":"render_html","arguments":{"code":"<html>"}'
)
assert not _detect_render_html_tool_start(
"<function=python><parameter=code>'<function=render_html>'"
)
assert not _detect_render_html_tool_start(
'<tool_call>{"name":"python","arguments":{"code":"<function=render_html>"}}'
)
def test_strip_markup_closed(self):
text = "before <tool_call>{}</tool_call> after"
assert strip_tool_markup(text) == "before after"
def test_strip_markup_unclosed_final(self):
text = "before <tool_call>{partial"
# final=True drops the trailing run.
assert strip_tool_markup(text, final = True) == "before"
# Without final=True the unclosed run is preserved.
assert "partial" in strip_tool_markup(text)
def test_streaming_strip_respects_disabled_healing(self):
raw = 'before <tool_call>{"name":"web_search"'
assert strip_tool_markup_streaming(raw, auto_heal_tool_calls = False) == raw
assert strip_tool_markup_streaming(raw) == "before "
def test_streaming_strip_respects_disabled_healing_without_tool_protocol(self):
raw = 'before <tool_call>{"name":"web_search"'
assert strip_tool_markup_streaming(raw, auto_heal_tool_calls = False) == raw
assert (
strip_tool_markup_streaming(
raw,
auto_heal_tool_calls = False,
tool_protocol_active = True,
)
== "before "
)
# ────────────────────────────────────────────────────────────────────
# run_safetensors_tool_loop
# ────────────────────────────────────────────────────────────────────
def _fake_stream(chunks):
"""Build a single-turn generator that yields cumulative snapshots."""
def _gen(_messages):
acc = ""
for c in chunks:
acc += c
yield acc
return _gen
def _const_stream(text):
"""A single-turn generator that yields one cumulative snapshot."""
def _gen(_messages):
yield text
return _gen
class FakeExecuteTool:
"""Stand-in for ``core.inference.tools.execute_tool``."""
def __init__(self, results):
# ``results`` is a list of strings or RuntimeError instances.
self.results = list(results)
self.calls: list[tuple[str, dict]] = []
def __call__(
self,
name,
arguments,
*,
cancel_event = None,
timeout = None,
session_id = None,
rag_scope = None,
):
self.calls.append((name, arguments))
result = self.results.pop(0) if self.results else "OK"
if isinstance(result, Exception):
raise result
return result
def _collect_events(generator, max_events = 200):
events = []
for ev in generator:
events.append(ev)
if len(events) >= max_events:
break
return events
def _make_loop(
*,
turns,
exec_results = None,
**kwargs,
):
"""Build a configured loop with a multi-turn fake generator.
``turns`` is a list of chunk-lists; iteration N yields chunks from ``turns[N]``.
"""
turn_iter = iter(turns)
def _gen(_messages):
try:
chunks = next(turn_iter)
except StopIteration:
return
acc = ""
for c in chunks:
acc += c
yield acc
exec_fn = FakeExecuteTool(exec_results or [])
return run_safetensors_tool_loop(
single_turn = _gen,
messages = [{"role": "user", "content": "hi"}],
tools = [
{"type": "function", "function": {"name": "web_search"}},
{"type": "function", "function": {"name": "python"}},
{"type": "function", "function": {"name": "terminal"}},
],
execute_tool = exec_fn,
**kwargs,
), exec_fn
def test_active_tools_are_passed_to_single_turn_after_render_html_success():
captured_tool_names: list[list[str]] = []
exec_fn = FakeExecuteTool(["Rendered HTML artifact."])
def fake_single_turn(_messages, *, active_tools = None):
captured_tool_names.append(
[
(tool.get("function") or {}).get("name")
for tool in (active_tools or [])
if (tool.get("function") or {}).get("name")
]
)
if len(captured_tool_names) == 1:
yield '<tool_call>{"name":"render_html","arguments":{"code":"<html>one</html>"}}</tool_call>'
else:
yield "Done."
events = _collect_events(
run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "make html"}],
tools = [
{"type": "function", "function": {"name": "render_html"}},
{"type": "function", "function": {"name": "web_search"}},
],
execute_tool = exec_fn,
max_tool_iterations = 3,
)
)
assert exec_fn.calls == [("render_html", {"code": "<html>one</html>"})]
assert captured_tool_names == [["render_html", "web_search"], ["web_search"]]
assert any(event.get("type") == "content" and event.get("text") == "Done." for event in events)
class TestLoopBasic:
def test_plain_answer(self):
# No tool XML; loop should yield content then status="".
loop, _exec = _make_loop(
turns = [["Hello", " world", "!"]],
exec_results = [],
)
events = _collect_events(loop)
contents = [e for e in events if e["type"] == "content"]
statuses = [e for e in events if e["type"] == "status"]
assert contents, "expected at least one content event"
# Final cumulative content must contain the answer.
final_text = contents[-1]["text"]
assert "Hello world!" in final_text
assert statuses and statuses[-1]["text"] == ""
def test_single_tool_then_answer(self):
loop, exec_fn = _make_loop(
turns = [
# Tool call only.
[
'<tool_call>{"name":"web_search",',
'"arguments":{"query":"weather"}}',
"</tool_call>",
],
# Final answer.
["The ", "weather is ", "sunny."],
],
exec_results = ["Sunny and 22C"],
)
events = _collect_events(loop)
kinds = [e["type"] for e in events]
assert "tool_start" in kinds
assert "tool_end" in kinds
# Tool was called with the parsed arguments.
assert exec_fn.calls == [("web_search", {"query": "weather"})]
tool_start = next(e for e in events if e["type"] == "tool_start")
assert tool_start["tool_name"] == "web_search"
tool_end = next(e for e in events if e["type"] == "tool_end")
assert tool_end["result"] == "Sunny and 22C"
contents = [e for e in events if e["type"] == "content"]
assert contents and "sunny" in contents[-1]["text"].lower()
def test_function_xml_form(self):
loop, exec_fn = _make_loop(
turns = [
["<function=python><parameter=code>print(1)</parameter></function>"],
["Result: 1"],
],
exec_results = ["1\n"],
)
events = _collect_events(loop)
assert exec_fn.calls == [("python", {"code": "print(1)"})]
contents = [e for e in events if e["type"] == "content"]
assert "Result: 1" in contents[-1]["text"]
def test_render_html_emits_provisional_tool_start(self):
exec_fn = FakeExecuteTool(["Rendered HTML artifact."])
turn_iter = iter(
[
[
"<function=render_html>",
"<parameter=code><!doctype html><html>",
"<body>Hi</body></html></parameter></function>",
],
["Done."],
]
)
def _gen(_messages):
chunks = next(turn_iter)
acc = ""
for chunk in chunks:
acc += chunk
yield acc
loop = run_safetensors_tool_loop(
single_turn = _gen,
messages = [{"role": "user", "content": "make html"}],
tools = [{"type": "function", "function": {"name": "render_html"}}],
execute_tool = exec_fn,
)
events = _collect_events(loop)
tool_starts = [e for e in events if e["type"] == "tool_start"]
assert len(tool_starts) == 2
assert tool_starts[0]["tool_name"] == "render_html"
assert tool_starts[0]["arguments"] == {}
assert tool_starts[1]["tool_name"] == "render_html"
assert "<!doctype html>" in tool_starts[1]["arguments"]["code"]
assert exec_fn.calls[0][0] == "render_html"
assert "<!doctype html>" in exec_fn.calls[0][1]["code"]
def test_python_tool_containing_render_html_signal_does_not_emit_provisional_start(self):
loop, exec_fn = _make_loop(
turns = [
[
"<function=python>",
"<parameter=code>print('<function=render_html>')",
"</parameter></function>",
],
["Done."],
],
exec_results = ["ok"],
)
events = _collect_events(loop)
tool_starts = [e for e in events if e["type"] == "tool_start"]
assert len(tool_starts) == 1
assert tool_starts[0]["tool_name"] == "python"
assert exec_fn.calls == [("python", {"code": "print('<function=render_html>')"})]
def test_render_html_success_blocks_second_artifact_call(self):
exec_fn = FakeExecuteTool(["Rendered HTML artifact."])
turn_iter = iter(
[
[
'<tool_call>{"name":"render_html",',
'"arguments":{"code":"<html>one</html>"}}',
],
[
'<tool_call>{"name":"render_html",',
'"arguments":{"code":"<html>two</html>"}}',
],
["Done."],
]
)
def _gen(_messages):
chunks = next(turn_iter)
acc = ""
for chunk in chunks:
acc += chunk
yield acc
loop = run_safetensors_tool_loop(
single_turn = _gen,
messages = [{"role": "user", "content": "make html"}],
tools = [{"type": "function", "function": {"name": "render_html"}}],
execute_tool = exec_fn,
)
events = _collect_events(loop)
tool_starts = [e for e in events if e["type"] == "tool_start"]
assert exec_fn.calls == [("render_html", {"code": "<html>one</html>"})]
assert [e["arguments"] for e in tool_starts] == [{}, {"code": "<html>one</html>"}]
def test_truncated_unclosed_tool_call(self):
loop, exec_fn = _make_loop(
turns = [
# No </tool_call>; balanced-brace parser still succeeds because
# the JSON itself is balanced.
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}'],
["done"],
],
exec_results = ["result"],
)
events = _collect_events(loop)
assert exec_fn.calls == [("web_search", {"query": "x"})]
def test_bad_json_healed_to_query(self):
# Non-JSON string arguments heal to {"query": ...} under auto_heal_tool_calls.
loop, exec_fn = _make_loop(
turns = [
# ``arguments`` is a string _coerce_arguments can't parse, so heal runs.
['<tool_call>{"name":"web_search","arguments":"hello world"}</tool_call>'],
["ok"],
],
exec_results = ["..."],
)
events = _collect_events(loop)
assert exec_fn.calls and exec_fn.calls[0][0] == "web_search"
assert exec_fn.calls[0][1] == {"query": "hello world"}
class TestLoopBehaviour:
def test_duplicate_tool_call_internal_noop(self):
captured_messages: list[list[dict]] = []
turns = iter(
[
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
["final"],
]
)
def fake_single_turn(messages):
captured_messages.append([dict(message) for message in messages])
chunks = next(turns)
acc = ""
for chunk in chunks:
acc += chunk
yield acc
exec_fn = FakeExecuteTool(["search-result-1"])
events = _collect_events(
run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "hi"}],
tools = [{"type": "function", "function": {"name": "web_search"}}],
execute_tool = exec_fn,
max_tool_iterations = 3,
)
)
assert exec_fn.calls == [("web_search", {"query": "x"})]
assert [e["tool_call_id"] for e in events if e["type"] == "tool_end"] == ["call_0"]
assert not [
e
for e in events
if e.get("tool_call_id") == "call_1" and e.get("type") in {"tool_start", "tool_end"}
]
duplicate_nudges = [
message
for message in captured_messages[-1]
if message.get("role") == "user"
and "already completed successfully" in message.get("content", "")
]
assert len(duplicate_nudges) == 1
def test_duplicate_tool_call_internal_noop_allows_distinct_followup_tool(self):
captured_messages: list[list[dict]] = []
captured_tool_names: list[list[str]] = []
turns = iter(
[
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
['<tool_call>{"name":"python","arguments":{"code":"print(1)"}}</tool_call>'],
["final"],
]
)
def fake_single_turn(messages, active_tools = None):
captured_messages.append([dict(message) for message in messages])
captured_tool_names.append(
[
tool["function"]["name"]
for tool in (active_tools or [])
if tool.get("function", {}).get("name")
]
)
chunks = next(turns)
acc = ""
for chunk in chunks:
acc += chunk
yield acc
exec_fn = FakeExecuteTool(["search-result-1", "python-result"])
events = _collect_events(
run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "hi"}],
tools = [
{"type": "function", "function": {"name": "web_search"}},
{"type": "function", "function": {"name": "python"}},
],
execute_tool = exec_fn,
max_tool_iterations = 4,
)
)
assert exec_fn.calls == [
("web_search", {"query": "x"}),
("python", {"code": "print(1)"}),
]
assert [e["tool_call_id"] for e in events if e["type"] == "tool_end"] == [
"call_0",
"call_2",
]
assert not [
e
for e in events
if e.get("tool_call_id") == "call_1" and e.get("type") in {"tool_start", "tool_end"}
]
duplicate_nudges = [
message
for message in captured_messages[2]
if message.get("role") == "user"
and "already completed successfully" in message.get("content", "")
]
assert len(duplicate_nudges) == 1
assert captured_tool_names[2] == ["web_search", "python"]
def test_repeated_duplicate_noop_transitions_to_final_attempt(self):
captured_tool_names: list[list[str]] = []
turns = iter(
[
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
["final from first result"],
]
)
def fake_single_turn(messages, active_tools = None):
captured_tool_names.append(
[
(tool.get("function") or {}).get("name")
for tool in (active_tools or [])
if (tool.get("function") or {}).get("name")
]
)
chunks = next(turns)
acc = ""
for chunk in chunks:
acc += chunk
yield acc
exec_fn = FakeExecuteTool(["search-result"])
events = _collect_events(
run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "hi"}],
tools = [{"type": "function", "function": {"name": "web_search"}}],
execute_tool = exec_fn,
max_tool_iterations = 10,
)
)
assert exec_fn.calls == [("web_search", {"query": "x"})]
assert [
event.get("tool_call_id") for event in events if event.get("type") == "tool_end"
] == ["call_0"]
assert captured_tool_names[-1] == []
assert any(
event.get("type") == "content" and "final from first result" in event.get("text", "")
for event in events
)
def test_kb_search_capped_per_turn(self):
# Paraphrased KB searches differ by args (dup guard misses them); the
# per-turn cap stops the runaway re-search loop.
n = RAG_MAX_SEARCHES_PER_TURN
queries = [f"paraphrase {i}" for i in range(n + 1)]
turns = [
[
'<tool_call>{"name":"search_knowledge_base",'
f'"arguments":{{"query":"{q}"}}}}</tool_call>'
]
for q in queries
] + [["final answer"]]
turn_iter = iter(turns)
def _gen(_messages):
try:
chunks = next(turn_iter)
except StopIteration:
return
acc = ""
for c in chunks:
acc += c
yield acc
exec_fn = FakeExecuteTool([f"chunk-{i}" for i in range(n)])
loop = run_safetensors_tool_loop(
single_turn = _gen,
messages = [{"role": "user", "content": "hi"}],
tools = [{"type": "function", "function": {"name": "search_knowledge_base"}}],
execute_tool = exec_fn,
)
events = _collect_events(loop)
assert len(exec_fn.calls) == n
assert all(c[0] == "search_knowledge_base" for c in exec_fn.calls)
tool_end_events = [e for e in events if e["type"] == "tool_end"]
assert len(tool_end_events) == n + 1
assert "do not search again" in tool_end_events[n]["result"].lower()
def test_image_sentinel_stripped_from_model_feed(self):
# The image sentinel is stripped before the next turn, but tool_end still
# carries the raw result for the UI.
loop, exec_fn = _make_loop(
turns = [
['<tool_call>{"name":"python","arguments":{"code":"plot()"}}</tool_call>'],
["see chart"],
],
exec_results = ["chart\n__IMAGES__:/tmp/chart.png"],
)
events = _collect_events(loop)
tool_end = next(e for e in events if e["type"] == "tool_end")
assert "__IMAGES__" in tool_end["result"]
def test_image_sentinel_stripped_with_leading_marker(self):
# Sentinel at start (no newline) must not leak to the model.
from core.inference import safetensors_agentic as _sa
captured: list[list[dict]] = []
def fake_single_turn(messages, **_kw):
captured.append([dict(m) for m in messages])
if len(captured) == 1:
yield '<tool_call>{"name":"python","arguments":{"code":"plot()"}}</tool_call>'
else:
yield "done"
events = list(
_sa.run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "plot please"}],
tools = [{"function": {"name": "python"}}],
execute_tool = lambda *_a, **_kw: "__IMAGES__:/tmp/x.png",
cancel_event = threading.Event(),
max_tool_iterations = 3,
auto_heal_tool_calls = True,
)
)
# The model's second turn must not see "__IMAGES__".
assert len(captured) >= 2
tool_msgs = [m for m in captured[1] if m.get("role") == "tool"]
assert tool_msgs, "no tool message reached the model"
for tm in tool_msgs:
assert "__IMAGES__" not in tm["content"], f"sentinel leaked to model: {tm['content']!r}"
def test_image_sentinel_stripped_with_multiple_markers(self):
# Consecutive sentinels: cut at the first, nothing leaks.
from core.inference import safetensors_agentic as _sa
captured: list[list[dict]] = []
def fake_single_turn(messages, **_kw):
captured.append([dict(m) for m in messages])
if len(captured) == 1:
yield '<tool_call>{"name":"python","arguments":{"code":"plot()"}}</tool_call>'
else:
yield "done"
multi = "panel\n__IMAGES__:/tmp/a.png\n__IMAGES__:/tmp/b.png"
events = list(
_sa.run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "plot please"}],
tools = [{"function": {"name": "python"}}],
execute_tool = lambda *_a, **_kw: multi,
cancel_event = threading.Event(),
max_tool_iterations = 3,
auto_heal_tool_calls = True,
)
)
tool_msgs = [m for m in captured[1] if m.get("role") == "tool"]
assert tool_msgs
for tm in tool_msgs:
assert "__IMAGES__" not in tm["content"], f"second sentinel leaked: {tm['content']!r}"
assert tm["content"] == "panel", f"expected payload-only 'panel', got {tm['content']!r}"
def test_tool_execution_error_is_emitted_but_loop_continues(self):
loop, exec_fn = _make_loop(
turns = [
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
["sorry, that failed"],
],
exec_results = ["Error: network unreachable"],
)
events = _collect_events(loop)
tool_end = next(e for e in events if e["type"] == "tool_end")
assert tool_end["result"].startswith("Error")
# The loop must still emit a content event after the failure.
contents = [e for e in events if e["type"] == "content"]
assert contents
def test_exception_in_executor_does_not_raise(self):
loop, exec_fn = _make_loop(
turns = [
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
["recovered"],
],
exec_results = [RuntimeError("boom")],
)
events = _collect_events(loop)
tool_end = next(e for e in events if e["type"] == "tool_end")
assert "boom" in tool_end["result"]
class TestLoopControl:
def test_cancel_event_breaks_loop(self):
cancel = threading.Event()
cancel.set()
# With cancel set, the loop bails before invoking execute_tool.
exec_fn = FakeExecuteTool([])
events = list(
run_safetensors_tool_loop(
single_turn = _const_stream(
'<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'
),
messages = [{"role": "user", "content": "hi"}],
tools = [],
execute_tool = exec_fn,
cancel_event = cancel,
)
)
assert events == []
assert exec_fn.calls == []
def test_max_iterations_caps_loop(self):
# The loop stops after max_tool_iterations even if the model keeps
# asking for tools, then emits a final-attempt round.
loop, exec_fn = _make_loop(
turns = [
# Tool call (executes once).
['<tool_call>{"name":"web_search","arguments":{"query":"a"}}</tool_call>'],
# Model gives a final answer when nudged.
["here is the final answer"],
],
exec_results = ["result"],
max_tool_iterations = 1,
)
events = _collect_events(loop)
contents = [e for e in events if e["type"] == "content"]
# Final content must contain the final answer.
assert contents and "final answer" in contents[-1]["text"]
class TestStatusFormatting:
def test_status_for_known_tools(self):
# Call the private helper directly to verify status formatting.
assert (
safetensors_agentic._status_for_tool("web_search", {"query": "abc"}) == "Searching: abc"
)
assert (
safetensors_agentic._status_for_tool("web_search", {"url": "https://www.example.com/x"})
== "Reading: example.com"
)
assert safetensors_agentic._status_for_tool("python", {"code": "x = 1"}).startswith(
"Running Python:"
)
assert safetensors_agentic._status_for_tool("terminal", {"command": "ls"}).startswith(
"Running:"
)
assert safetensors_agentic._status_for_tool("unknown_tool", {}).startswith("Calling:")
class TestProseMentioningToolCall:
def test_assistant_prose_with_literal_tool_call_text_survives(self):
# Regression: prose that mentions a literal ``<tool_call>`` (no real call)
# must surface in full, not be stripped past the marker.
loop, exec_fn = _make_loop(
turns = [
# A real tool call so the loop advances a turn.
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
# Prose that mentions the literal text.
["the docs say <tool_call> means an LLM tool call wrapper"],
],
exec_results = ["result"],
)
events = _collect_events(loop)
contents = [e for e in events if e["type"] == "content"]
assert contents, "expected at least one content event"
final = contents[-1]["text"]
assert (
"LLM tool" in final
), f"prose mentioning <tool_call> should not be truncated; got {final!r}"
def test_tool_result_with_tool_call_text_does_not_retrigger(self):
# A literal ``<tool_call>`` in the tool result must not re-trigger: the
# loop parses only model output, so exactly one call.
loop, exec_fn = _make_loop(
turns = [
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
["the docs mention <tool_call> wrappers"],
],
exec_results = ["Page text: <tool_call> appears here in the docs"],
)
events = _collect_events(loop)
assert len(exec_fn.calls) == 1
class TestChatTemplateHelper:
"""Cover the dependency-light helper used by InferenceBackend."""
def setup_method(self):
from core.inference.chat_template_helpers import (
apply_chat_template_for_generation,
)
self.apply = apply_chat_template_for_generation
class _Tok:
def __init__(self, accepted):
self.accepted = accepted
self.call_count = 0
self.last_kwargs = None
def apply_chat_template(
self,
messages,
*,
tokenize = False,
add_generation_prompt = True,
**kw,
):
self.call_count += 1
unknown = set(kw) - self.accepted
if unknown:
raise TypeError(f"unexpected kwargs: {sorted(unknown)}")
self.last_kwargs = dict(kw)
return "PROMPT"
def test_richest_call_wins_when_template_supports_all(self):
tok = self._Tok({"tools", "enable_thinking"})
self.apply(tok, [], tools = [{}], enable_thinking = True)
assert tok.call_count == 1
assert tok.last_kwargs is not None
assert "tools" in tok.last_kwargs
assert "enable_thinking" in tok.last_kwargs
def test_falls_back_when_template_rejects_reasoning_kwarg(self):
tok = self._Tok({"tools"})
self.apply(tok, [], tools = [{}], enable_thinking = True)
assert tok.call_count >= 2
assert tok.last_kwargs == {"tools": [{}]}
def test_falls_back_to_bare_call(self):
tok = self._Tok(set())
self.apply(tok, [], tools = [{}], enable_thinking = True)
assert tok.last_kwargs == {}
def test_jinja_error_propagates(self):
class Boom:
def apply_chat_template(self, *a, **kw):
raise ValueError("jinja: missing var")
with pytest.raises(ValueError):
self.apply(Boom(), [])
def test_no_kwargs_single_call(self):
tok = self._Tok(set())
self.apply(tok, [])
assert tok.call_count == 1
# ────────────────────────────────────────────────────────────────────
# Guardrails (allowlist, budget, streaming-leak, dedup, id offset,
# auto_heal=False, canonical healed-arg key)
# ────────────────────────────────────────────────────────────────────
class TestGuardrails:
def test_disabled_tool_is_not_executed(self):
captured_messages: list[list[dict]] = []
def fake_single_turn(messages):
captured_messages.append([dict(message) for message in messages])
if len(captured_messages) == 1:
yield '<tool_call>{"name":"terminal","arguments":{"command":"echo bypass"}}</tool_call>'
else:
yield "final"
exec_fn = FakeExecuteTool([])
events = _collect_events(
run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "hi"}],
tools = [{"type": "function", "function": {"name": "web_search"}}],
execute_tool = exec_fn,
max_tool_iterations = 2,
)
)
assert exec_fn.calls == []
assert not [event for event in events if event.get("type") in {"tool_start", "tool_end"}]
disabled_nudges = [
message
for message in captured_messages[-1]
if message.get("role") == "user" and "not enabled" in message.get("content", "")
]
assert len(disabled_nudges) == 1
def test_empty_tools_list_means_allow_all_in_core_loop(self):
turns = iter(
[
['<tool_call>{"name":"python","arguments":{"code":"print(1)"}}</tool_call>'],
["done"],
]
)
def fake_single_turn(_messages, active_tools = None):
assert active_tools == []
acc = ""
for chunk in next(turns):
acc += chunk
yield acc
exec_fn = FakeExecuteTool(["OK"])
events = _collect_events(
run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "hi"}],
tools = [],
execute_tool = exec_fn,
max_tool_iterations = 2,
)
)
assert exec_fn.calls == [("python", {"code": "print(1)"})]
assert any(event.get("type") == "tool_end" for event in events)
def test_max_iterations_zero_executes_no_tools(self):
loop, exec_fn = _make_loop(
turns = [['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>']],
exec_results = ["OK"],
max_tool_iterations = 0,
)
events = _collect_events(loop)
assert exec_fn.calls == []
assert events and events[-1] == {"type": "status", "text": ""}
def test_streaming_clips_before_tool_signal_no_leak(self):
loop, exec_fn = _make_loop(
turns = [
[
"I will look this up. ",
"Some more prose that's long enough to leave the buffer. ",
'<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>',
],
["all done"],
],
exec_results = ["weather: sunny"],
max_tool_iterations = 2,
)
events = _collect_events(loop)
assert exec_fn.calls == [("web_search", {"query": "x"})]
for e in events:
if e["type"] == "content":
assert "<tool_call>" not in e["text"]
assert "web_search" not in e["text"]
def test_auto_heal_disabled_still_parses_valid_tool_call(self):
loop, exec_fn = _make_loop(
turns = [
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
["done"],
],
exec_results = ["OK"],
auto_heal_tool_calls = False,
max_tool_iterations = 2,
)
_collect_events(loop)
assert exec_fn.calls == [("web_search", {"query": "x"})]
def test_auto_heal_disabled_preserves_xml_on_final_no_tools_pass(self):
turns = iter(
[
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}</tool_call>'],
['<tool_call>{"name":"web_search","arguments":{"query":"literal"}}</tool_call>'],
]
)
def fake_single_turn(_messages, active_tools = None):
acc = ""
for chunk in next(turns):
acc += chunk
yield acc
exec_fn = FakeExecuteTool(["OK"])
events = _collect_events(
run_safetensors_tool_loop(
single_turn = fake_single_turn,
messages = [{"role": "user", "content": "show literal"}],
tools = [{"type": "function", "function": {"name": "web_search"}}],
execute_tool = exec_fn,
max_tool_iterations = 1,
auto_heal_tool_calls = False,
)
)
assert exec_fn.calls == [("web_search", {"query": "x"})]
assert any(
event.get("type") == "content" and "<tool_call>" in event.get("text", "")
for event in events
)
def test_auto_heal_disabled_does_not_repair_unclosed_tool_call(self):
loop, exec_fn = _make_loop(
turns = [
['<tool_call>{"name":"web_search","arguments":{"query":"x"}}'],
],
exec_results = ["OK"],
auto_heal_tool_calls = False,
max_tool_iterations = 1,
)
events = _collect_events(loop)
assert exec_fn.calls == []
assert any(
event.get("type") == "content" and "<tool_call>" in event.get("text", "")
for event in events
)
def test_auto_heal_enabled_strips_unparseable_xml_tool_call(self):
loop, exec_fn = _make_loop(
turns = [["<tool_call>{not valid json}</tool_call>"]],
exec_results = ["OK"],
auto_heal_tool_calls = True,
max_tool_iterations = 1,
)
events = _collect_events(loop)
assert exec_fn.calls == []
assert not any(
event.get("type") == "content" and "<tool_call>" in event.get("text", "")
for event in events
)
def test_non_consecutive_duplicate_is_short_circuited(self):
loop, exec_fn = _make_loop(
turns = [
['<tool_call>{"name":"web_search","arguments":{"query":"A"}}</tool_call>'],
['<tool_call>{"name":"web_search","arguments":{"query":"B"}}</tool_call>'],
['<tool_call>{"name":"web_search","arguments":{"query":"A"}}</tool_call>'],
["final"],
],
exec_results = ["res-A", "res-B"],
max_tool_iterations = 4,
)
events = _collect_events(loop)
assert exec_fn.calls == [("web_search", {"query": "A"}), ("web_search", {"query": "B"})]
assert [
event.get("tool_call_id") for event in events if event.get("type") == "tool_end"
] == ["call_0", "call_1"]
assert not [
event
for event in events
if event.get("tool_call_id") == "call_2"
and event.get("type") in {"tool_start", "tool_end"}
]
def test_same_turn_duplicate_is_short_circuited(self):
loop, exec_fn = _make_loop(
turns = [
[
'<tool_call>{"name":"web_search","arguments":{"query":"A"}}</tool_call>'
'<tool_call>{"name":"web_search","arguments":{"query":"A"}}</tool_call>'
],
["final"],
],
exec_results = ["res-A"],
max_tool_iterations = 2,
)
events = _collect_events(loop)
assert exec_fn.calls == [("web_search", {"query": "A"})]
assert [
event.get("tool_call_id") for event in events if event.get("type") == "tool_end"
] == ["call_0"]
assert not [
event
for event in events
if event.get("tool_call_id") == "call_1"
and event.get("type") in {"tool_start", "tool_end"}
]
def test_coerce_string_args_python_uses_code_key(self):
assert _coerce_arguments("print(1)", heal = True, tool_name = "python") == {"code": "print(1)"}
def test_coerce_string_args_terminal_uses_command_key(self):
assert _coerce_arguments("ls -la", heal = True, tool_name = "terminal") == {"command": "ls -la"}
def test_tool_call_ids_unique_across_loop_iterations(self):
loop, _exec = _make_loop(
turns = [
['<tool_call>{"name":"web_search","arguments":{"query":"A"}}</tool_call>'],
['<tool_call>{"name":"web_search","arguments":{"query":"B"}}</tool_call>'],
["done"],
],
exec_results = ["A", "B"],
max_tool_iterations = 3,
)
events = _collect_events(loop)
ids = [e["tool_call_id"] for e in events if e["type"] == "tool_start"]
assert len(ids) == 2 and ids[0] != ids[1]
# ────────────────────────────────────────────────────────────────────
# Shared gpt-oss name detector
# ────────────────────────────────────────────────────────────────────
class TestGptOssNameDetection:
def test_substring_match(self):
assert is_gpt_oss_model_name("unsloth/gpt-oss-20b") is True
def test_negative_known_non_oss_model(self):
assert is_gpt_oss_model_name("meta-llama/Llama-3.1-8B-Instruct") is False
def test_empty_or_none_returns_false(self):
assert is_gpt_oss_model_name("") is False
assert is_gpt_oss_model_name(cast(str, None)) is False
if __name__ == "__main__":
pytest.main([__file__, "-v"])