deepseek-harness/python/sdk/README.md

# DeepSeek Harness Python SDK

English | [中文](README.zh.md)

Python subprocess SDK for driving DeepSeek Harness over newline-delimited JSON-RPC on stdio. Install `deepseek-harness-sdk`; it installs the exact same-version `deepseek-harness-runtime-bin` wheel for the current platform.

```sh
python -m pip install deepseek-harness-sdk
```

## Optional Office operations

Download the Office runtime explicitly, then call the local API without an agent, Session, model request, API key, or Harness home:

```py
from deepseek_harness_runtime import download_office
from deepseek_harness.office import convert, recalculate, render_images

download_office()
pdf = convert("report.docx", "report.pdf")
workbook = recalculate("forecast.xlsx", "calculated.xlsx")
preview = render_images("report.docx", "report-preview", pages=[1])
```

The output file or image directory must not exist. Successful outputs belong to the caller; Kit removes failed outputs. `OfficeOptions` supplies operation limits and font preferences. Results expose typed paths, missing fonts, and image metadata. `OfficeError` retains CLI failure codes; malformed results raise `SdkProtocolError`. Recalculation does not verify business logic or Excel fidelity. Ctrl+C waits for CLI cleanup; a second interrupt forces termination and may leave partial output. Windows requires an absolute `SystemRoot` and a shared console for Ctrl+C delivery.

The authoring environment is independently optional through `deepseek_harness_runtime.download_primary_runtime()`. See the [runtime reference](../sdk-runtime/README.md) for cache selection, resource activation, and download behavior. SDK startup and Office operations never acquire missing resources automatically.

## Start a runtime

The Python SDK has no separate application entrypoint. It launches the bundled `dsh` CLI with `--profile sdk`; the selected profile owns the JSON-RPC server, agent composition, credentials, persistence, tools, and shutdown behavior.

Every launch requires an explicit Harness home. Pass `dsh_home` or provide a non-empty `DSH_HOME` in the child environment. The SDK deliberately never discovers `~/.dsh`.

```py
from deepseek_harness import DeepSeekHarness

with DeepSeekHarness(
    dsh_home="/absolute/path/to/isolated-dsh-home",
    cwd="/absolute/path/to/workspace",
    provider="deepseek-official",
    model="deepseek-v4-flash",
    reasoning_effort="max",
    max_tokens=49_152,
) as harness:
    result = harness.run("Say hi.", session_id="example-001")

print(result.final_response)
```

`DeepSeekHarness` starts lazily and reuses its runtime until `close()` or context-manager exit. The initial profile handshake has an independent 30-second default bound through `initialize_timeout_seconds`; ordinary turns remain unbounded unless `request_timeout_seconds` is set. A timeout names the selected profile and includes retained runtime diagnostics. `cwd` is the agent workspace; `runtime_cwd` independently selects the subprocess working directory. Both become absolute before launch. `provider`, `model`, optional `reasoning_effort`, and optional positive `max_tokens` are sent during JSON-RPC initialization. `base_url` and `api_key` explicitly override `DEEPSEEK_BASE_URL` and `DEEPSEEK_API_KEY` in the child environment.

`harness.resume_session(saved_session_id)` restores persisted history and returns a `Session` ready for `run()`. Save the original session id and reuse its `dsh_home` and workspace. Restoration preserves the stored directory, repairs an interrupted final turn, and sends no new input. Missing, unreadable, incompatible, or occupied sessions raise without creating a replacement. `start_session(id)` only opens a lazy handle; it does not request persisted restoration. This API does not restore shell, browser, or other external processes.

```py
with DeepSeekHarness(dsh_home="/absolute/path/to/saved-home") as harness:
    session = harness.resume_session(saved_session_id)
    result = session.run("Continue the task.")
```

## Customize plugins

Persistent customization belongs to a `dsh` profile. Initialize the shipped SDK profile and install an external bundle with the runtime wheel's `dsh` command:

```sh
export DSH_HOME=/absolute/path/to/isolated-dsh-home
dsh --profile sdk --dump-default-config >/dev/null
dsh plugin --profile sdk add file:/absolute/path/to/my-plugin-bundle
```

The `file:` form installs the local bundle into the profile package tree, where its peer imports reach the bundled installation fallback. The profile manifest records installed dependencies and ordered bundle layers; its `$DSH_HOME/profiles/sdk/cordis.patch.yml` is the persistent user patch. `dsh plugin` needs `pnpm` only when managing external packages. Running the SDK does not require system Node.js.

For an invocation-specific change, pass one or more patch files. They become absolute and are forwarded in order after the profile and home patch layers:

```py
with DeepSeekHarness(
    dsh_home="/absolute/path/to/isolated-dsh-home",
    profile="sdk",
    patches=("/absolute/path/to/first.patch.yml", "/absolute/path/to/last.patch.yml"),
) as harness:
    result = harness.run("Make the requested code change.")
```

`profile` may select another existing profile, but that composition must retain `@deepseek-ai/dsh-sdk-app` or another `@deepseek-ai/dsh-sdk-jsonrpc-server` row. Misconfiguration fails during CLI boot or SDK initialization; there is no complete-config fallback. `dsh_bin` may select another `dsh` executable while preserving the same profile grammar. Arbitrary argv replacement remains an internal fake-runtime test adapter, not public API.

`provider` selects a provider route registered by the chosen Cordis composition; `model` is the model id resolved by that adapter. `reasoning_effort` is an optional non-empty adapter-owned identifier for that exact route; omission preserves the model's own default. `max_tokens` is an optional positive per-request output-token cap for the root agent and its in-process descendants; omission leaves the provider default in control. Initialization rejects a missing adapter, unavailable model, or unsupported effort before a prompt runs. Compaction summaries keep the separate limit configured by their compaction plugin. The bundled default composition registers `deepseek-official`. A custom composition can mount `llm-pi-ai`, configure provider-specific credentials/endpoints there, and select any provider/model present in pi-ai's installed catalog.

The shipped `sdk-minimal` profile is a standalone explicit tree rather than an overlay on `dsh-base`. Select it with `profile="sdk-minimal"`; the ordinary `model` argument is the sole runtime model selection, including for model ids outside the adapter's advisory catalog. It provides a platform-selected persistent shell, `read_image`, `working_directory`, local execution, JSONL sessions, and automatic compaction. Text file tools, settings, managed credentials, telemetry, Web tools, and the full default tool roster remain available through the separate full `sdk` and `web` profiles. SDK prompt text does not execute `/compact`.

## Native user questions

Pass `on_user_question` to `DeepSeekHarnessConfig`, `DeepSeekHarness`, or `HarnessConfig` to answer the built-in `ask_user_question` tool through the native SDK protocol. The callback receives a `UserQuestionRequest` (`request_id`, `session_id`, and the original `questions`) and a `threading.Event` signalling cancellation. Return `UserQuestionAnswer` or a JSON object shaped as `{"answers": [{"id": "question-id", "selected": ["option label"], "custom": "optional free text"}]}`. Each original question id must appear exactly once. The application supplies its UI or simulated-user policy; the SDK does not choose answers.

Callbacks run on separate threads so the reader can process cancellation and other requests. They may run concurrently and may make further client requests. Release callback-owned work when the cancellation Event is set. Closing the client signals outstanding callbacks and gives their workers a shared 0.5-second join window; callbacks that ignore cancellation may continue, but their late answers cannot reach the runtime or a later process. A callback exception becomes a protocol error, and an absent callback retains existing native answerers or reports `NO_PROVIDER`.

## Results and notifications

`Session.run()` owns an activity interval from its prompt's durable inbox receipt through the next whole-agent idle and returns `RunResult(session_id, final_response, finish_reason, events, notifications)`. `final_response` is the last committed root-session assistant text in the interval. `finish_reason` is the `kind` of the last root-session `turn/end`, such as `completed`, `max-tokens`, or `error`, and is `None` when no turn ended. A `turn/end` without a string `data.reason.kind` violates the protocol and raises `SdkProtocolError`.

`HarnessClient` retains discovered subagent ancestry for the runtime process lifetime. During `Session.run()`, `RunResult.notifications` and `on_notification` receive the root session and known descendants in wire order. `RunResult.events` contains root-session events only, so descendant output cannot replace the root response. The low-level `session_prompt()` returns the queued message id immediately; callers that bypass `Session.run()` own the later activity boundary.

The selected home stores profiles, plugins, and every profile-owned durable resource. The full `sdk` profile uses its credentials, settings, and session stores; `sdk-minimal` uses JSONL session storage and stores images under `$DSH_HOME/attachments/v1`, with request-image cache under `$DSH_HOME/cache/attachments`. Use a fresh home when those resources must be isolated, and a fresh session id for independent work. Reusing both a harness and session id continues the durable conversation and session-owned resources.

See the [Python tutorial](../../docs/user/guide/python-sdk.md), [runnable example](examples/README.md), and [runtime wheel reference](../sdk-runtime/README.md).

`Session.get_working_directory()` reads the effective working directory; `set_working_directory(path)` changes it and returns the validated absolute path. Both create an unknown Session without running a model turn. Relative paths use that Session's current directory. Origin metadata, permissions, and existing processes remain unchanged. The low-level client provides the same methods with a leading `session_id` argument.