Agent-as-Tool

JamJet lets you wrap any agent as a callable tool inside a workflow. Three invocation modes cover different use cases — from quick lookups to long-running analyses to multi-turn conversations.

Three Modes

Sync

Single request, single response. Best for fast, stateless operations.

graph.add_agent_tool("classifier",
    agent="https://classifier-agent.example.com",
    mode="sync",
    timeout_ms=5000,
)

Posts to /tasks/send and returns the full response as the node output.

Streaming

Incremental NDJSON processing with real-time event emission. Best for long-running agents where you want progress visibility, budget control, and early termination.

graph.add_agent_tool("researcher",
    agent="https://research-agent.example.com",
    mode="streaming",
    budget={"max_cost_usd": 0.50},
    streaming={"idle_timeout_secs": 30},
)

Posts to /tasks/sendSubscribe and processes the NDJSON stream incrementally:

• Real-time events — each chunk is emitted to the state backend as it arrives, not batched at the end
• Idle timeout — if no data arrives within idle_timeout_secs (default 30), the stream is terminated
• Budget guard — when accumulated cost_usd from chunks exceeds max_cost_usd, the stream stops
• A2A cancel — on early termination (budget or timeout), a best-effort tasks/cancel is sent to the remote agent
• Partial results preserved — chunks already emitted are never lost, even on failure

Conversational

Multi-turn exchange for iterative refinement. The coordinator sends input, reads the response, and feeds it back as the next turn's input.

graph.add_agent_tool("editor",
    agent="https://editor-agent.example.com",
    mode={"conversational": {"max_turns": 5}},
)

Posts to /tasks/send in a loop. Stops when the agent responds with status: "completed" or max_turns is reached.

Streaming Configuration

For streaming mode, the per-chunk idle timeout replaces the overall HTTP timeout. The client is built without a global timeout so long-running streams with active data aren't killed prematurely.

Events

The agent tool emits structured events to the event log:

Each event includes timestamp_ms for precise timing. Progress events include chunk_index and accumulated_cost_usd.

Error Handling

Hard failures (timeout, network error) cause the node to fail so the workflow can retry or handle the error. Budget breach is also treated as a failure.

Protocol Resolution

The agent URI determines the protocol:

Example

See the agent-as-tool example for a complete workflow using all three modes.