feat(DATAGO-114389): PR 4: Workflow Tool for Agents

[efunneko]

PR 4: Workflow Tool for Agents

Overview

This PR provides an ADK Tool implementation that allows agents to invoke workflows as tools. This creates a bridge between LLM-driven agent orchestration and prescriptive workflows, enabling agents to call deterministic workflows when needed.

Branch Information

• Branch Name: pr/workflows-4-workflow-tool
• Target: pr/workflows-3-agent-support

Files Changed

src/solace_agent_mesh/agent/tools/workflow_tool.py

The WorkflowAgentTool class (~370 lines) provides:

Method	Purpose
__init__()	Initialize tool from workflow agent card
_get_declaration()	Generate ADK FunctionDeclaration from schema
run_async()	Main execution entry point
_prepare_input_artifact()	Create input artifact from args
_prepare_a2a_message()	Construct A2A message for workflow
_submit_task()	Send message and register for response
_poll_for_result()	Wait for workflow completion

Key Features

• Dynamic tool generation: Tool definition is generated from workflow's input schema
• Dual-mode invocation: Supports both direct parameters and artifact reference
• Long-running execution: Uses ADK long-running tool pattern
• Async polling: Waits for workflow completion via correlation ID

Tool Discovery Flow

When a workflow publishes its agent card with input/output schemas:

1. SamAgentComponent receives agent card via discovery
2. If agent card has schema extension, create WorkflowAgentTool
3. Tool is added to agent's available tools
4. LLM can now invoke the workflow via the tool

Invocation Modes

# Mode 1: Direct parameters
await workflow_process_order(
    customer_id="12345",
    items=["widget", "gadget"]
)

# Mode 2: Artifact reference
await workflow_process_order(
    input_artifact="order_data.json"
)

Message Flow

1. Agent LLM decides to call workflow tool
2. Tool validates input against schema
3. Tool creates input artifact
4. Tool sends A2A message to workflow
5. Tool polls for response via correlation ID
6. Tool returns workflow output to agent

Key Concepts

Tool Naming Convention

Workflow tools are named with prefix workflow_:

workflow_process_order
workflow_data_pipeline

Correlation for Response Matching

Sub-task correlation IDs link requests to responses:

a2a_subtask_<uuid>

Schema-to-ADK Translation

The tool dynamically converts JSON Schema to ADK types:

JSON Schema Type	ADK Type
string	Type.STRING
integer	Type.INTEGER
number	Type.NUMBER
boolean	Type.BOOLEAN
array	Type.ARRAY
object	Type.OBJECT

[alimosaed]

LG

[alimosaed]

this is not used anywhere