LangGraph 1.2.17: our test log

LangGraph 1.2.17 passed our one-tool task on a local 3B model: 3 of 3 trials; cold uv install 2.5 s.

Tested by us on 2026-10-25. Local open-weight model, not the vendor's hosted models. A smoke test on a CPU-only box, not a benchmark.

Result at a glance

LangGraph test record
FieldValue
ResultPassed
Version tested1.2.17
Date and time2026-10-25, 23:16 to 23:16 CDT (America/Chicago)
TaskGive a local model one Python function, add_numbers(a, b), and ask it to use that tool to compute 17 + 25 and report the result. Pass means the function was called with 17 and 25 and the final answer contains 42. Three trials per tool, all on the same local model.
Model usedQwen2.5-3B-Instruct (Q4_K_M) through Ollama 0.40.11
HardwareLinux x86_64 virtual machine (Debian 13), 8 vCPU (Intel Xeon, 1 thread per core), 15 GiB RAM, no GPU
Installed size (uv)76 MB in 43 packages
Install time (uv, cold)2.5 s
Install time (pip, cold)8.1 s
Installed size (pip)121 MB in 44 packages
Task trials passed3 of 3
Task wall time (median, includes imports)3.2 s (range 3.2 to 3.4 s)
Machine load during trials7.0 to 7.1 (1-minute load average, 8 vCPU)

What we found

  • 3 of 3 task trials passed: the model's tool call reached the framework, the function ran with 17 and 25, and the final answer contained 42.
  • Cold install took 2.5 s with uv and 8.1 s with pip, and left 76 MB in 43 packages (uv).
  • Used the prebuilt ReAct agent helper rather than a hand-built graph, so this tests the shortest documented path, not custom graph features such as checkpoints or human-in-the-loop interrupts.

What we ran, step by step

Commands run, wall-clock time and exit code
StepWall timeExit codeNotes
Install with uv (cold, no cache)2.5 s0Machine load average before the run: 0.90.
Install with pip (cold, no cache)8.1 s0Load average before: 1.58. Second run; the first pip run was discarded (see the research page).
Task command (all trials)n/an/aRun from a directory that contains common.py (shown below). Telemetry switches were set for tools that have them.
Task trial 13.2 s0Tool called with [[17, 25]]; answer: The result of adding 17 and 25 is 42. Load 7.00.
Task trial 23.2 s0Tool called with [[17, 25]]; answer: The result of adding 17 and 25 is 42. Load 7.08.
Task trial 33.4 s0Tool called with [[17, 25]]; answer: The result of adding 17 and 25 is 42. Load 7.08.
Exact commands (paths shortened)
# Install with uv (cold, no cache)
uv venv -q -p 3.13 work/py/langgraph && VIRTUAL_ENV=work/py/langgraph uv pip install --no-cache -q langgraph langchain-openai

# Install with pip (cold, no cache)
uv venv -q --seed -p 3.13 work/pip/langgraph && work/pip/langgraph/bin/pip install --no-cache-dir -q langgraph langchain-openai

# Task command (all trials)
OTEL_SDK_DISABLED=true work/py/langgraph/bin/python tasks/langgraph_react.py

Raw output (excerpts)

tasks/langgraph_react.py, the whole script for this test
from common import *
from langgraph.prebuilt import create_react_agent
from langchain_openai import ChatOpenAI
agent = create_react_agent(ChatOpenAI(model=MODEL, base_url=BASE, api_key=KEY, temperature=0), tools=[add_numbers])
r = agent.invoke({"messages":[{"role":"user","content":TASK}]})
report(r["messages"][-1].content)
common.py, the shared helper every framework script imports
import json, os
BASE = "http://127.0.0.1:11434/v1"
MODEL = os.environ.get("MODEL", "qwen2.5-3b")
KEY = "ollama"
TASK = "Use the add_numbers tool to compute 17 + 25, then tell me the result."
CALLS = []
def add_numbers(a: int, b: int) -> int:
    """Add two integers and return the sum."""
    CALLS.append((a, b))
    return int(a) + int(b)
def report(final):
    ok = any({int(x), int(y)} == {17, 25} for x, y in CALLS) and "42" in str(final)
    print("RESULT_JSON " + json.dumps({"calls": CALLS, "final": str(final)[:300], "ok": ok}))
Result line printed by trial 1 (2026-10-25 23:16:49 CDT)
RESULT_JSON {"calls": [[17, 25]], "final": "The result of adding 17 and 25 is 42.", "ok": true}

What we did not test

  • Any vendor-hosted model: everything ran on a local 3B model, so tool-call reliability with frontier models is not measured here.
  • Multi-agent flows, memory, long conversations, streaming, tracing and cloud deployment.
  • Anything beyond one tool and one question; three trials is a smoke test, not a benchmark.

Reproduce it

Versions change. These commands install whatever is latest on the day you run them unless a version is pinned, so expect different results later. The version we measured is in the table above.

# 1. Serve any local model that supports tool calling behind an OpenAI-compatible endpoint, registered as qwen2.5-3b:
#    http://127.0.0.1:11434/v1  (we used Ollama with a Qwen2.5-3B-Instruct Q4_K_M GGUF)
uv venv -p 3.13 .venv && VIRTUAL_ENV=.venv uv pip install langgraph langchain-openai
# 2. Save common.py (above) and the task script next to each other, then:
.venv/bin/python langgraph_react.py

How to read this test

Every number on this page was measured on this one machine, which also ran other jobs, so timings are indicative and vary run to run. A pass means our small task worked once or as stated, a fail means it did not work as we ran it; neither says how the tool behaves with a vendor's frontier model, on a GPU, or at scale. Where a tool could not run without an account or a GPU, we say so instead of guessing.

See the testing rig for the hardware, the local model and the rules we follow, and the test hub for every other test.

  • LiteLLM: LiteLLM 1.106.4 passed our one-tool task on a local 3B model: 3 of 3 trials; cold uv install 2.3 s.
  • LlamaIndex: LlamaIndex 0.14.25 passed our one-tool task on a local 3B model: 3 of 3 trials; cold uv install 3.4 s.
  • Mastra: Mastra passed 5 of 5 on Node 20 (0.24.9) and 5 of 5 on Node 24 (1.79.0) with temperature pinned to 0, after failing 5 of 6 earlier trials at default sampling.
  • Mem0: Mem0's open-source SDK 2.2.1 stored a fact from one chat message with a local 3B model and retrieved it with a semantic search (2.04 s) on the second attempt; the first two runs failed on a missing package and an API change.
  • OpenAI Agents SDK (Python): OpenAI Agents SDK (Python) 0.24.0 passed our one-tool task on a local 3B model: 3 of 3 trials; cold uv install 1.7 s.
  • OpenAI Agents SDK for JavaScript: OpenAI Agents SDK for JS (0.21.0) passed 2 of 5 (Node 20) and 1 of 5 (Node 24) at default sampling but 5 of 5 on both Node versions once temperature was pinned to 0.

All test logs · How we test

FAQ

Does LangGraph work with a local model?

In our run it did for this one task: 3 of 3 trials passed against a local Qwen2.5-3B model served by Ollama. We did not test other models, and results depend heavily on the model's tool-calling ability.

How big is a fresh LangGraph install?

76 MB in 43 packages with uv on 1.2.17, measured on 2026-10-25.

Sources

Markdown version for agents: /tests/langgraph.md