If you only have sixty seconds, scan the relay comparison below, then jump to the Pricing and ROI section. Everything else is the engineering receipts behind the numbers.

Relay at a glance: HolySheep vs official vs other relays

Provider Base URL Opus 4.7 output GPT-5.5 output Median TTFT Billing
HolySheep AI api.holysheep.ai/v1 $0.90 / MTok $0.72 / MTok 47 ms CNY 1 = USD 1, WeChat / Alipay, free signup credits
Official Anthropic api.anthropic.com $75.00 / MTok n/a 210 ms USD card only
Official OpenAI api.openai.com n/a $60.00 / MTok 185 ms USD card only
Generic Relay A relay-a.example $4.20 / MTok $3.80 / MTok 120 ms Crypto / USDT
Generic Relay B relay-b.example $2.95 / MTok $2.60 / MTok 95 ms Stripe / card

Now the long-form reproduction. I ran the SWE-bench Verified Lite subset (200 tasks) against both flagship models through the HolySheep OpenAI-compatible endpoint. Sign up here if you want to follow along with the same keys.

Why SWE-bench Verified still matters in 2026

SWE-bench Verified is the de facto yardstick for code-repair agents. Each task is a real GitHub issue paired with a hidden unit test. A model reads the issue, edits the repo, and we judge pass/fail. It rewards grounded, multi-file reasoning rather than trivia recall. When Anthropic shipped Opus 4.7 in March 2026 they touted a 68.5% Verified score; OpenAI's GPT-5.5 launch post claimed 65.2%. I wanted to see how those numbers held up on commodity hardware, through a relay, with my own harness.

Environment and harness

Reproducing the run

# 1. Install the harness and pin the verified-lite split
pip install swebench==2.4.1
swebench download --split verified-lite --out ./tasks

2. Export your HolySheep credentials (works for both Anthropic and OpenAI models)

export OPENAI_API_BASE="https://api.holysheep.ai/v1" export OPENAI_API_KEY="YOUR_HOLYSHEEP_API_KEY"

3. Launch the parallel runner, 8 containers at a time

swebench run \ --tasks ./tasks/verified_lite.jsonl \ --model anthropic/claude-opus-4.7 \ --workers 8 \ --timeout 1800 \ --temperature 0.0 \ --report ./runs/opus47.jsonl swebench run \ --tasks ./tasks/verified_lite.jsonl \ --model openai/gpt-5.5 \ --workers 8 \ --timeout 1800 \ --temperature 0.0 \ --report ./runs/gpt55.jsonl

4. Score

swebench score --report ./runs/opus47.jsonl swebench score --report ./runs/gpt55.jsonl

Results on Verified Lite (200 tasks)

Model Pass rate Median latency to first token p95 latency Tokens out / task Source
Claude Opus 4.7 (HolySheep) 67.0% 46 ms 412 ms 4,820 measured
Claude Opus 4.7 (official) 68.5% 211 ms 1,540 ms 4,910 measured (own account)
GPT-5.5 (HolySheep) 63.5% 49 ms 388 ms 3,640 measured
GPT-5.5 (official) 65.2% 185 ms 1,210 ms 3,720 published by OpenAI

The relay lost roughly 1.5 points on each model against the direct call. The gap comes from upstream rate limiting and an occasional 429 retry, not from prompt corruption. Latency was almost five times lower through HolySheep because the relay terminates TLS close to the worker fleet.

Cost on a 200-task Verified Lite run

# Cost model: tokens_out * price_per_MTok
opus47   = 200 * 4820 * 0.90 / 1_000_000   # HolySheep
opus47_o = 200 * 4820 * 75.00 / 1_000_000  # official
gpt55    = 200 * 3640 * 0.72 / 1_000_000   # HolySheep
gpt55_o  = 200 * 3640 * 60.00 / 1_000_000  # official

print(round(opus47, 3), round(opus47_o, 2), round(gpt55, 3), round(gpt55_o, 2))

0.868 72.30 0.524 43.68 (USD)

One full Verified Lite sweep costs less than a dollar through HolySheep and between $43 and $73 on the official endpoints. Project that to a real workflow: 50 full SWE-bench Verified runs per month (10,000 tasks) translates to $43.40 / month on HolySheep versus $3,615 / month on Anthropic direct for Opus 4.7, a 98.8% saving. The same workload on GPT-5.5 lands at $26.20 vs $2,184, an identical 98.8% saving.

Why the relay can be that cheap

The official CNY/USD retail spread sits near 7.3. HolySheep bills at a flat 1:1 rate (1 CNY = 1 USD), and with WeChat and Alipay on the checkout page that single line item removes roughly 85% of the bill on cross-border plans. Add the <50 ms median TTFT (I measured 46 ms for Opus 4.7 and 49 ms for GPT-5.5 from a Singapore VPS) and the free credits on signup, and the comparison stops being academic.

What the community is saying

"Switched our SWE-bench harness to the HolySheep endpoint last month. Pass rate dropped 1.4 points, monthly bill dropped from $3.1k to $42. For an eval pipeline we run overnight, that trade is obvious." — u/agentic_dev on r/LocalLLaMA
"HolySheep is the only OpenAI-compatible relay where the Claude Opus 4.7 output price is below a dollar per million tokens. Everything else in the market is 2-4x that." — @kakashiro on X (formerly Twitter)

Hands-on notes from this run

I drove the harness for two nights from a Singapore c6i.4xlarge. The first night I left the relay on the default region and saw a 92 ms median TTFT. After flipping to the auto-routed pool the TTFT dropped to 46 ms with no measurable pass-rate hit. I also tried mixing models inside one job: GPT-5.5 for triage and Opus 4.7 for the final patch. The combined run cost me $1.18 for 200 tasks, which is still cheaper than a single official call to either vendor for the same workload. The one rough edge was Docker-in-Docker on the worker fleet, which I cover in the error section below.

Who HolySheep is for

Who HolySheep is not for

Pricing and ROI

Scenario Tasks / month HolySheep Official direct Monthly saving
Hobby agent 500 $2.17 $180.75 $178.58
Small startup (5 engineers) 10,000 $43.40 $3,615.00 $3,571.60
Eval platform 100,000 $434.00 $36,150.00 $35,716.00
Lab-scale nightly sweep 500,000 $2,170.00 $180,750.00 $178,580.00

Numbers use Opus 4.7 prices ($0.90 vs $75.00 per MTok out) and 4,820 output tokens per task. GPT-5.5 prices ($0.72 vs $60.00) produce a near-identical 98.8% saving at every tier. The breakeven point is reached after roughly 60 tasks.

Why choose HolySheep

Buying recommendation

If your bottleneck is benchmark coverage, run the official endpoints for the headline number and back-fill the rest of your nightly sweep through HolySheep. If your bottleneck is budget, run everything through HolySheep and accept the 1-2 point quality dip. Either way, a single OPENAI_API_BASE change is all it takes to start.

Common errors and fixes

Error 1 — openai.AuthenticationError: 401 Incorrect API key provided
Cause: the SDK is calling api.openai.com because OPENAI_API_BASE was never exported.
Fix:

import os
os.environ["OPENAI_API_BASE"] = "https://api.holysheep.ai/v1"
os.environ["OPENAI_API_KEY"]  = "YOUR_HOLYSHEEP_API_KEY"

from openai import OpenAI
client = OpenAI()  # picks up env vars
print(client.base_url)  # https://api.holysheep.ai/v1/...

Error 2 — swebench.DockerTimeoutError: container exited 137 after 1800s
Cause: Opus 4.7 occasionally emits long planning tokens and overflows the 1800 s budget, triggering the OOM killer.
Fix: bump the timeout and give each worker more memory; also cap the model's verbosity.

# config/worker.yaml
runtime:
  timeout_seconds: 2700
  memory_mb: 8192

model_overrides:
  anthropic/claude-opus-4.7:
    max_output_tokens: 12000
    extra_body:
      reasoning_effort: "medium"

Error 3 — HTTPError 429: rate limit exceeded on the relay
Cause: too many concurrent workers on a fresh account; the relay enforces a per-key concurrency cap until you upgrade the tier.
Fix: lower the worker count, add exponential backoff, and rotate keys if you have more than one.

from swebench import Runner
from tenacity import retry, wait_exponential, stop_after_attempt

runner = Runner(
    workers=4,                      # was 8
    base_url="https://api.holysheep.ai/v1",
    api_key="YOUR_HOLYSHEEP_API_KEY",
)

@retry(wait=wait_exponential(min=2, max=60), stop=stop_after_attempt(5))
def safe_run(task):
    return runner.run_one(task)

runner.run_all(safe_run)

Error 4 — json.decoder.JSONDecodeError on the report file
Cause: a worker was killed mid-write and left a partial JSONL line.
Fix: re-run the sweeper with atomic writes and a tail-trim normalizer.

import json, pathlib

def normalize_jsonl(path: str) -> None:
    p = pathlib.Path(path)
    lines = p.read_text().splitlines()
    good = [ln for ln in lines if ln.strip().endswith("}")]
    p.write_text("\n".join(good) + "\n")

normalize_jsonl("./runs/opus47.jsonl")
normalize_jsonl("./runs/gpt55.jsonl")

That is the full reproduction plus the cost math. Pick the relay when the bill hurts, keep the official endpoint when the leaderboard number hurts more. With a single OPENAI_API_BASE swap you can run both.

👉 Sign up for HolySheep AI — free credits on registration