Python client library for communicating with a runtimeuse agent runtime over WebSocket.
Handles the WebSocket connection lifecycle, message dispatch, artifact upload handshake, cancellation, and structured result parsing -- so you can focus on what to do with agent results rather than wire protocol details.
pip install runtimeuse-clientStart the runtime inside any sandbox, then connect from outside:
import asyncio
from runtimeuse_client import (
AssistantMessageInterface,
QueryOptions,
RuntimeEnvironmentDownloadableInterface,
RuntimeUseClient,
StructuredOutputResult,
TextResult,
)
WORKDIR = "/runtimeuse"
async def main():
# Start the runtime in a sandbox (provider-specific)
sandbox = Sandbox.create()
sandbox.run("npx -y runtimeuse@latest")
ws_url = sandbox.get_url(8080)
client = RuntimeUseClient(ws_url=ws_url)
async def on_assistant(msg: AssistantMessageInterface) -> None:
for block in msg.text_blocks:
print(f"[assistant] {block}")
# Text response (no output schema)
result = await client.query(
prompt="Summarize the contents of the codex repository and list your favorite file in the repository.",
options=QueryOptions(
system_prompt="You are a helpful assistant.",
model="gpt-4.1",
on_assistant_message=on_assistant,
pre_agent_downloadables=[
RuntimeEnvironmentDownloadableInterface(
download_url="https://github.com/openai/codex/archive/refs/heads/main.zip",
working_dir=WORKDIR,
)
],
),
)
assert isinstance(result.data, TextResult)
print(result.data.text)
# Structured response (with output schema)
result = await client.query(
prompt="Inspect the codex repository and return the total file count and total character count across all files as JSON.",
options=QueryOptions(
system_prompt="You are a helpful assistant.",
model="gpt-4.1",
pre_agent_downloadables=[
RuntimeEnvironmentDownloadableInterface(
download_url="https://github.com/openai/codex/archive/refs/heads/main.zip",
working_dir=WORKDIR,
)
],
output_format_json_schema_str="""
{
"type": "json_schema",
"schema": {
"type": "object",
"properties": {
"file_count": { "type": "integer" },
"char_count": { "type": "integer" }
},
"required": ["file_count", "char_count"],
"additionalProperties": false
}
}
""",
),
)
assert isinstance(result.data, StructuredOutputResult)
print(result.data.structured_output)
print(result.metadata) # execution metadata
asyncio.run(main())For local development without a sandbox, connect directly:
client = RuntimeUseClient(ws_url="ws://localhost:8080")Manages the WebSocket connection to the agent runtime and runs the message loop: sends a prompt, iterates the response stream, and returns a QueryResult. Raises AgentRuntimeError if the runtime returns an error.
query() returns a QueryResult with .data (a TextResult or StructuredOutputResult) and .metadata.
client = RuntimeUseClient(ws_url="ws://localhost:8080")
result = await client.query(
prompt="Summarize the contents of the codex repository.",
options=QueryOptions(
system_prompt="You are a helpful assistant.",
model="gpt-4.1",
pre_agent_downloadables=[downloadable], # optional
output_format_json_schema_str='...', # optional -- omit for text response
on_assistant_message=on_assistant, # optional
on_artifact_upload_request=on_artifact, # optional -- return ArtifactUploadResult
timeout=300, # optional -- seconds
),
)
if isinstance(result.data, TextResult):
print(result.data.text)
elif isinstance(result.data, StructuredOutputResult):
print(result.data.structured_output)
print(result.metadata) # execution metadataUse execute_commands() when you need to run shell commands in the sandbox without invoking the agent. This is useful for setup steps, health checks, or any workflow where you only need command exit codes.
from runtimeuse_client import (
CommandInterface,
ExecuteCommandsOptions,
RuntimeUseClient,
)
client = RuntimeUseClient(ws_url="ws://localhost:8080")
result = await client.execute_commands(
commands=[
CommandInterface(command="mkdir -p /app/output"),
CommandInterface(command="echo 'sandbox is ready' > /app/output/status.txt"),
CommandInterface(command="cat /app/output/status.txt"),
],
options=ExecuteCommandsOptions(
on_assistant_message=on_assistant, # optional -- streams stdout/stderr
),
)
for item in result.results:
print(f"{item.command} -> exit code {item.exit_code}")execute_commands() supports the same streaming, cancellation, timeout, secret redaction, artifact upload, and error semantics as query(). If any command exits non-zero, AgentRuntimeError is raised.
When the agent runtime requests an artifact upload, provide a callback that returns a presigned URL and content type. The client sends the response back automatically.
from runtimeuse_client import ArtifactUploadResult
async def on_artifact(request: ArtifactUploadRequestMessageInterface) -> ArtifactUploadResult:
presigned_url = await my_storage.create_presigned_url(request.filename)
content_type = guess_content_type(request.filename)
return ArtifactUploadResult(presigned_url=presigned_url, content_type=content_type)When using artifact uploads, set both artifacts_dir and on_artifact_upload_request in QueryOptions; the client validates that they are provided together.
Call client.abort() from any coroutine to cancel a running query. The client sends a cancel message to the runtime and query raises CancelledException.
from runtimeuse_client import CancelledException
async def cancel_after_delay(client, seconds):
await asyncio.sleep(seconds)
client.abort()
try:
asyncio.create_task(cancel_after_delay(client, 30))
result = await client.query(
prompt="Do the thing.",
options=QueryOptions(
system_prompt="You are a helpful assistant.",
model="gpt-4.1",
),
)
except CancelledException:
print("Run was cancelled")| Class | Description |
|---|---|
QueryOptions |
Configuration for client.query() (prompt options, callbacks, timeout) |
QueryResult |
Return type of query() (.data, .metadata) |
ResultMessageInterface |
Wire-format result message from the runtime |
TextResult |
Result variant when no output schema is specified (.text) |
StructuredOutputResult |
Result variant when an output schema is specified (.structured_output) |
AssistantMessageInterface |
Intermediate assistant text messages |
ArtifactUploadRequestMessageInterface |
Runtime requesting a presigned URL for artifact upload |
ArtifactUploadResponseMessageInterface |
Response with presigned URL sent back to runtime |
ErrorMessageInterface |
Error from the agent runtime |
ExecuteCommandsOptions |
Configuration for client.execute_commands() (callbacks, timeout) |
CommandExecutionResult |
Return type of execute_commands() (.results) |
CommandResultItem |
Per-command result (.command, .exit_code) |
CommandInterface |
Shell command to execute (.command, .cwd) |
RuntimeEnvironmentDownloadableInterface |
File to download into the runtime before invocation |
| Class | Description |
|---|---|
AgentRuntimeError |
Raised when the agent runtime returns an error (carries .error and .metadata) |
CancelledException |
Raised when client.abort() is called during a query |