promptstore-telemetry (Python SDK)

Fail-safe agentic-harness observability for promptstore. Emits canonical spans (loops, tool calls, sub-agents, model calls, context-lifecycle events) to a promptstore telemetry endpoint.

Safety guarantees

This SDK is designed so that promptstore can never impact your application:

• Non-blocking — spans are enqueued to a bounded in-memory buffer and flushed by a background daemon thread.
• Never raises into your code — every telemetry operation is guarded. Your own exceptions inside a with span(...) still propagate (and are recorded as an error status).
• Bounded memory — under backpressure the buffer drops the oldest spans.
• Circuit breaker — repeated failures open a breaker and the SDK stops trying (and stops buffering) until a cooldown elapses.
• Zero runtime dependencies — standard library only.

Install

From PyPI:

pip install promptstore-telemetry

Requires Python 3.10+. The SDK has zero runtime dependencies (standard library only).

Pin a version for reproducible builds:

pip install "promptstore-telemetry==0.1.0"

Or add it to your project:

# pyproject.toml
dependencies = ["promptstore-telemetry>=0.1.0"]

# requirements.txt
promptstore-telemetry>=0.1.0

From source

To develop against a checkout of this repo (editable install):

pip install -e sdk/python          # add [dev] for the test extras: pip install -e "sdk/python[dev]"

Usage

import promptstore_telemetry as ps

ps.configure(base_url="https://promptstore.example.com", api_key="pst_...")
# or set PROMPTSTORE_URL and PROMPTSTORE_TELEMETRY_KEY

with ps.trace("research-agent") as run:
    for turn in range(max_turns):
        with ps.span(ps.SpanKind.LOOP_ITERATION, f"turn-{turn}"):
            with ps.span(ps.SpanKind.MODEL_CALL, "plan") as m:
                m.set_model(provider="anthropic", response_model="claude-3-5-sonnet-20241022")
                m.set_usage(prompt_tokens=1200, completion_tokens=300, cached_tokens=800)

            # context lifecycle — powers the Context view (budget chart,
            # composition, change cards). Include sources=[...] for full
            # per-source attribution; see docs/telemetry-sdk.md
            # ("Instrumenting context") and examples/multi_agent.py.
            ps.context_event(ps.ContextEventName.COMPACT,
                             sources=[{"source": "history", "tokens": 30000,
                                       "label": "summary of earlier turns"}],
                             window_tokens_before=180000, window_tokens_after=90000,
                             window_limit=200000,
                             tokens_reclaimed=90000, method="summarize")

@ps.tool("web_search")
def web_search(q): ...

# sub-agents across processes
with ps.subagent("researcher") as sub:
    traceparent = ps.get_traceparent()   # hand to the child process

Conversations (multi-turn, human-in-the-loop)

A multi-turn chat is modelled as one run: each user turn is a LOOP_ITERATION and waiting on the user is a first-class HITL_PAUSE span (its duration is the user's think-time). It shows as a single row in Harness Traces with status active / awaiting user / done, and the waterfall shows each turn separated by a "waiting for user" pause. Ids are derived from your conversation id, so turns in separate processes/requests stitch into the same run with no shared state:

# per incoming user message for `conv_id`, at turn index `n`:
with ps.conversation(conv_id, close_on_exit=False):
    ps.hitl_pause_close(index=n - 1)          # the user just replied
    with ps.turn(index=n):
        with ps.span(ps.SpanKind.MODEL_CALL, "respond") as m:
            m.set_usage(prompt_tokens=1000, completion_tokens=120)
    ps.hitl_pause_open(index=n)               # yield back to the user
# when the conversation ends:
ps.end_conversation(conv_id)

For a single long-lived loop that owns the whole conversation, keep the block open and let the default close_on_exit=True close it. A conversation parked on an open HITL_PAUSE is exempt from the stale-run reaper. See docs/telemetry-sdk.md.

Get a write-only telemetry key from promptstore: POST /api/workspaces/:workspaceId/telemetry-keys.

Configuration

configure(base_url, api_key, *, flush_interval=2.0, max_batch=128, max_buffer=10000, emit_on_start=True, timeout=5.0, circuit_fail_threshold=5, circuit_cooldown=30.0, redactor=None, deny_keys=None, session_id=None, enabled=True)

• emit_on_start — also emit a span when it opens (enables the live view). The server upserts start+end into one row.
• redactor / deny_keys — PII redaction hooks applied to attributes and event payloads before they leave the process.
• session_id — default conversation/session id stamped on every span; usually set per-conversation via ps.conversation(...) instead.