strand-sdk

Python client for the Strand Platform — H&E → multiplex protein inference.

Agent-friendly docs: The full API reference is published as Markdown at https://app.strandai.com/docs/api.md, and the LLM index lives at https://app.strandai.com/llms.txt.

pip install strand-sdk
# or with bioinformatics extras (AnnData / zarr):
pip install "strand-sdk[anndata]"

If your environment can't reach PyPI, you can install directly from the repository as a fallback:

pip install "git+https://github.com/Strand-AI/strand-sdk-python.git"

Quickstart

One blocking call runs the full pipeline — upload, submit, wait, download:

from strand import Client

client = Client(api_key="sk-strand-...")
result = client.predict(
    "biopsy.ome.tiff",
    markers=["HER2", "CD8", "PD1"],
    output_dir="./outputs/",
)
print(f"Used {result.credits_used} credits; wrote {len(result.marker_outputs)} markers")

client.predict(...) returns a PredictResult with job_id, status, credits_used, marker_outputs (paths under output_dir), and results (a JobResults handle for selective reads). It raises JobFailedError if the job fails, JobTimeoutError if the deadline elapses, and surfaces InsufficientCreditsError / RateLimitError on submit issues.

Pass on_progress=lambda stage, frac: ... to follow the four stages ("upload", "submit", "wait", "download").

Lower-level primitives

client.predict is also a namespace, so the underlying steps stay available for fine-grained control:

upload = client.uploads.upload_file("slide.svs")
estimate = client.predict.estimate(upload.id, markers=["CD3", "CD8", "Ki67"])
print(f"Will cost ≈ {estimate.estimated_credits} credits")

job = client.predict.submit(upload.id, markers=["CD3", "CD8", "Ki67"])
job.wait()                                    # blocks until terminal status
adata = job.download_results()                # AnnData

Configuration

Source	Variable / argument	Default
Env	STRAND_API_KEY	required
Env	STRAND_BASE_URL	https://app.strandai.com
Arg	Client(api_key=..., base_url=..., timeout=..., max_retries=...)	—

Layout

src/strand/
  __init__.py        public surface re-exports
  _client.py         Client (top-level)
  _uploads.py        uploads namespace (incl. resumable chunked upload helper)
  _predict.py        predict namespace — `client.predict(...)` (full pipeline) + `.estimate` / `.submit`
  _jobs.py           Job (wait / stream_events / download_results)
  _results.py        OME-Zarr v3 download + AnnData conversion
  _models.py         user-facing snake_case dataclasses
  _http.py           internal httpx wrapper with typed error mapping
  _errors.py         typed exceptions
openapi.json         pinned snapshot of the platform spec (drift-check)

Verifying against the platform OpenAPI spec

Transport is hand-written for ergonomic snake_case fields and AnnData integration. To check the SDK against an updated spec:

# regenerate a reference client and diff the request/response surface
uv tool run --from "openapi-python-client>=0.21" --with "click<8.2" \
    openapi-python-client generate \
    --path openapi.json \
    --output-path /tmp/strand-sdk-ref \
    --meta none --overwrite

To refresh openapi.json itself against a live server:

curl https://app.strandai.com/api/v1/openapi.json -o openapi.json
# or against local dev:
# curl http://localhost:3000/api/v1/openapi.json -o openapi.json

Development

uv sync --all-extras
uv run pytest
uv run ruff check src tests
uv run mypy src

Issues & contributing

File bug reports and feature requests at Strand-AI/strand-sdk-python/issues.

We don't accept external pull requests on the SDK at this time. If you'd like to contribute or have ideas you'd like to discuss, email support@strandai.com.

License

Apache 2.0