keylightdigital-nexus 0.1.0

Python SDK for Nexus — simple, affordable agent observability

keylightdigital-nexus

Python SDK for Nexus — simple, affordable AI agent observability.
The Plausible of AI agents. $9/month. No self-hosting.

Install

pip install keylightdigital-nexus

No dependencies beyond the Python standard library.

Quickstart

from nexus_agent import NexusClient

client = NexusClient(api_key="nxs_...", agent_id="my-agent")

trace = client.start_trace("process-invoice")
span = trace.add_span("call-llm", input={"prompt": "..."}, output={"text": "..."})
trace.end("success")

Get your API key at nexus.keylightdigital.dev.

API

NexusClient(api_key, agent_id, base_url?)

Parameter	Type	Description
api_key	str	API key from the Nexus dashboard (nxs_…)
agent_id	str	Human-readable agent name (groups traces in the dashboard)
base_url	str	Override API endpoint (default: https://nexus.keylightdigital.dev)

client.start_trace(name, metadata?) → Trace

Creates a new trace with status running. Call trace.end() when your agent finishes.

trace.add_span(name, input?, output?, error?) → Span

Records a unit of work. Timing is captured automatically at call time.

trace.end(status)

Finalizes the trace. status must be one of: "success", "error", "timeout".

Error handling

All network errors are caught internally and logged via Python's logging module.
Methods never raise — your agent keeps running even if Nexus is unreachable.

Python version support

Python 3.8 and above. No third-party dependencies.

License

MIT — see LICENSE.