Multi-Agent Orchestration¶

When agent.multiAgent is enabled, Lango replaces the single monolithic agent with a hierarchical agent tree. An orchestrator delegates tasks to specialized sub-agents based on keyword matching and a structured decision protocol.

Architecture¶

graph TD
    User([User]) --> O[lango-orchestrator]
    O --> OP[operator]
    O --> NAV[navigator]
    O --> V[vault]
    O --> LIB[librarian]
    O --> AUTO[automator]
    O --> PLAN[planner]
    O --> CHR[chronicler]
    O --> RA[Remote A2A Agents]

    style O fill:#4a9eff,color:#fff
    style PLAN fill:#9b59b6,color:#fff
    style RA fill:#e67e22,color:#fff

The orchestrator has no tools of its own. It receives user messages, classifies them, and transfers execution to the appropriate sub-agent via transfer_to_agent.

Sub-Agent Roles¶

Agent Details¶

operator¶

Executes system-level operations. Handles shell commands, file read/write, and skill invocation. Reports raw results including exit codes.

Cannot: web browsing, cryptographic operations, payment transactions, knowledge search, memory management.

navigator¶

Browses the web. Navigates to pages, interacts with elements (click, type, scroll), and takes screenshots. Returns page content with current URL and title.

Cannot: shell commands, file operations, cryptographic operations, payment transactions, knowledge search.

vault¶

Handles security-sensitive operations. Encrypts/decrypts data, manages secrets and passwords, signs/verifies, and processes blockchain payments (USDC on Base).

Cannot: shell commands, web browsing, file operations, knowledge search, memory management.

librarian¶

Manages the knowledge layer. Searches information, queries RAG indexes, traverses the knowledge graph, saves knowledge and learnings, manages skills, and handles proactive knowledge inquiries. See Proactive Librarian for details on the inquiry system.

Cannot: shell commands, web browsing, cryptographic operations, memory management (observations/reflections).

automator¶

Manages automation systems. Schedules recurring cron jobs, submits background tasks, and runs multi-step workflow pipelines.

Cannot: shell commands, file operations, web browsing, cryptographic operations, knowledge search.

planner¶

Decomposes complex tasks into clear, actionable steps and designs execution plans. Uses LLM reasoning only -- has no tools. This agent is always included in the agent tree even when no tools match its prefix.

Cannot: executing commands, web browsing, file operations, any tool-based operations.

chronicler¶

Manages conversational memory. Records observations, creates reflections, and recalls past interactions. Returns memories with context and timestamps.

Cannot: shell commands, web browsing, file operations, knowledge search, cryptographic operations.

Tool Partitioning¶

Tools are assigned to sub-agents based on their name prefix. The matching order is:

1. librarian -- checked first because save_knowledge, save_learning, create_skill, and list_skills are exact-match prefixes that must not fall through to operator
2. chronicler -- memory_*, observe_*, reflect_*
3. automator -- cron_*, bg_*, workflow_*
4. navigator -- browser_*
5. vault -- crypto_*, secrets_*, payment_*
6. operator -- exec_*, fs_*, skill_*
7. unmatched -- tools matching no prefix are tracked separately and listed in the orchestrator prompt

Sub-agents with no matching tools are skipped (not created), except for the planner which is always included.

Routing Protocol¶

The orchestrator follows a 5-step decision protocol before delegating:

1. CLASSIFY  -- Identify the domain of the request
2. MATCH     -- Compare keywords against the routing table
3. SELECT    -- Choose the best-matching agent
4. VERIFY    -- Check the selected agent's "Cannot" list for conflicts
5. DELEGATE  -- Transfer to the selected agent via transfer_to_agent

Each sub-agent has a keyword list used for routing:

Rejection Handling¶

Sub-agents can reject misrouted tasks by responding with:

[REJECT] This task requires <correct_agent>. I handle: <capability list>.

When a rejection occurs, the orchestrator re-evaluates and tries the next most relevant agent.

Delegation Limits¶

The orchestrator enforces a maximum number of delegation rounds per user turn (default: 5). Simple conversational messages (greetings, opinions, general knowledge) are handled directly by the orchestrator without delegation.

Remote A2A Agents¶

When A2A protocol is enabled, remote agents are appended to the sub-agent list and appear in the routing table. The orchestrator can delegate to them just like local sub-agents.

Configuration¶

Settings: lango settings → Multi-Agent

{
  "agent": {
    "multiAgent": true
  }
}

CLI Commands¶

Agent Status¶

lango agent status

Shows whether multi-agent mode is enabled, the orchestrator name, and the number of active sub-agents.

Agent List¶

lango agent list

Lists all active sub-agents with their roles, tool counts, and capabilities.