The product

One SDK to build, run, and observe production agents.

Synapse OSS is the runtime, durability, and signal pipeline — Apache 2.0 today. Synapse Cloud brings hosted infra and framework enablement for Claude Code Agents, LangChain, and CrewAI. In private preview.

Agent(), @tool(), parent-child delegation. ReAct loop and provider abstraction (Anthropic + OpenAI) built in.

from synapse import Agent, tool

@tool()
def delegate_to_writer(brief: str):
  return await writer.run(brief)

researcher = Agent(tools=[search, delegate_to_writer], monitor=True)
# child runs auto-link to parent trace

from synapse import Agent, tool

@tool()
def delegate_to_writer(brief: str):
  return await writer.run(brief)

researcher = Agent(tools=[search, delegate_to_writer], monitor=True)
# child runs auto-link to parent trace

Trajectories persisted. Reruns are idempotent — same inputs hit cached steps; only changes re-execute. Replay any run from any step. Sticky A/B variant assignment per user/session.

$ synapse run replay run_a8c12f --from-step=3
# prior steps cached, no double-spend

$ synapse experiment ab \
  --variant prompt-v2 --traffic 0.5
# sticky variant assignment by user/session

$ synapse run replay run_a8c12f --from-step=3
# prior steps cached, no double-spend

$ synapse experiment ab \
  --variant prompt-v2 --traffic 0.5
# sticky variant assignment by user/session

MonitorPipeline classifies every completed run against eight named signals. Slack + webhook alerts. Semantic trace search. PII redaction on ingest.