[FEATURE] Add support for A2A registry

[sigent]

Problem Statement

I would like Strands to support the A2A Registry community project (https://a2a-registry.dev/) by providing a comprehensive tool that enables agents to discover, search, and communicate with other agents through a centralized registry. The
tool should provide the following functionality:

1. Agent Discovery & Search:
   • Find agents by specific skills using registry_find_agents_by_skill(skill_id)
   • Get all registered agents with registry_get_all_agents()
   • Find the best agent for a task based on required skills using registry_find_best_agent_for_task(required_skills)
   • Find similar agents based on skill overlap using registry_find_similar_agents(reference_agent_id)

2. Agent Communication:
   • Send messages to specific agents via registry_send_message_to_agent(agent_name, message_text, message_id)
   • Find and message agents in one operation using registry_find_and_message_agent(required_skills, message_text)

3. Registry Integration:
   • Connect to configurable registry URLs (default: http://localhost:8000)
   • Use JSON-RPC 2.0 protocol for registry communication
   • Support multiple transport protocols (HTTP JSON, JSON-RPC, and custom transports)
   • Handle authentication for secure agent communication
   • Cache agent cards for performance optimization

4. Advanced Features:
   • Support for skill-based agent matching and ranking
   • Similarity scoring based on skill overlap
   • Configurable timeouts and error handling
   • Comprehensive logging and debugging support
   • Support for both synchronous and asynchronous operations

This tool would enable Strands agents to participate in the broader A2A ecosystem, allowing them to discover specialized agents for specific tasks and coordinate complex multi-agent workflows through the centralized registry.

Proposed Solution

No response

Use Case

Agentic Use Cases for A2A Registry Tool

1. Autonomous Task Delegation

An AI agent autonomously identifies it lacks specific capabilities and finds specialized agents:
python

Agent realizes it needs legal expertise for contract analysis

result = agent.tool.registry_find_and_message_agent(
required_skills=["legal_analysis", "contract_review"],
message_text="I need help analyzing this software licensing agreement for compliance risks"
)

2. Self-Organizing Agent Swarms

Agents autonomously form temporary coalitions for complex projects:
python

Lead agent assembles a development team

backend_agents = agent.tool.registry_find_agents_by_skill("backend_development")
frontend_agents = agent.tool.registry_find_agents_by_skill("frontend_development")

Agents coordinate without human intervention

3. Intelligent Workload Distribution

Agents make autonomous decisions about task routing based on current capacity:
python

Agent evaluates multiple specialists and selects optimal one

best_analyst = agent.tool.registry_find_best_agent_for_task(
required_skills=["financial_modeling", "risk_assessment"]
)

4. Adaptive Failure Recovery

Agents automatically find replacements when collaborators become unavailable:
python

Agent detects partner failure and finds similar capabilities

backup_agents = agent.tool.registry_find_similar_agents("failed_data_processor")

Seamlessly continues workflow with new partner

5. Emergent Specialization Networks

Agents discover and connect with complementary specialists to form expertise networks:
python

Medical AI agent finds diagnostic specialists

radiology_agents = agent.tool.registry_find_agents_by_skill("medical_imaging")
pathology_agents = agent.tool.registry_find_agents_by_skill("pathology_analysis")

6. Autonomous Market Making

Agents create dynamic service marketplaces by discovering supply and demand:
python

Translation agent finds clients needing language services

content_creators = agent.tool.registry_find_agents_by_skill("content_creation")
agent.tool.registry_send_message_to_agent(
agent_name=content_creators["agents"][0]["name"],
message_text="I offer real-time translation services for your multilingual content"
)

7. Self-Healing System Architecture

Agents proactively identify and recruit redundant capabilities for system resilience:
python

Infrastructure agent ensures backup services are available

all_agents = agent.tool.registry_get_all_agents()

Agent analyzes system topology and fills capability gaps

8. Cognitive Load Balancing

Agents redistribute cognitive tasks based on current mental workload and expertise:
python

Overloaded research agent delegates subtasks

analysis_specialists = agent.tool.registry_find_best_agent_for_task(
required_skills=["statistical_analysis", "data_visualization"]
)

9. Autonomous Quality Assurance

Agents independently seek peer review and validation from qualified specialists:
python

Code-writing agent finds reviewers for quality control

security_experts = agent.tool.registry_find_agents_by_skill("security_audit")
performance_experts = agent.tool.registry_find_agents_by_skill("performance_optimization")

10. Emergent Innovation Networks

Agents form research collaborations by discovering complementary research interests:
python

AI research agent finds collaboration partners

ml_researchers = agent.tool.registry_find_agents_by_skill("machine_learning_research")

Agents autonomously propose joint research projects

Alternatives Solutions

No response

Additional Context

No response