TICKETIQ

Sub-agents

Let a managed agent delegate work to specialist sub-agents that spend its budget and inherit its limits, or run under tighter limits of their own.

After reading this page you will be able to:
  • Add a sub-agent with its own description and instructions
  • Limit the tools a sub-agent can use
  • Give a sub-agent its own context budget, reply cap, step cap and run limits
  • Explain what stops delegation loops

A managed agent can hand part of a task to a sub-agent: a new one defined on the parent, or an existing agent picked from the registry. The parent's model sees each sub-agent's description and decides when to call it.

Prerequisites

  • A managed agent (sub-agents are not available on self-managed agents).

Add a sub-agent

  1. Open the parent agent's Settings tab and go to the Tools section, where its runtime is.
  2. Under Subagents, type a name (lowercase letters, digits and hyphens) and choose Add subagent to define a new one, or pick an agent and choose Add registered agent to reuse an existing one.
  3. Fill in the fields.
    FieldNotes
    DescriptionWhat the parent reads to decide to use it. Be specific about when, not just what.
    InstructionsThe sub-agent's own brief. New sub-agents only.
    Context it is givenTask only, Handoff note (the parent writes one) or Last 6 turns of this conversation. Passed context counts against the budget.
    Model override / Provider overrideOptional, new sub-agents only. Blank inherits the parent's. Use a cheaper model for narrow tasks. A provider override needs a model.
    Its MCP serversNew sub-agents only. Each tool list is held to what the parent itself may use on the same server.
    Context budget (context_budget_tokens)Optional, new sub-agents only. The input one of its steps may send, 1,024 to 2,000,000 tokens, held to its own model's window when it runs. Blank uses the parent's budget.
    Reply cap (max_tokens)Optional, new sub-agents only. The most tokens one of its replies may have, 1 to 32,000 and never more than its model can generate. Blank uses the reply cap the parent's run has.
    Step cap (max_iterations)Optional, new sub-agents only. How many model calls one delegation may make, 1 to 100 and never more than the parent's. Blank uses the parent's.
    Run limits (limits)Optional, new sub-agents only. The same keys as the parent's per-run limits (max_seconds, max_tool_calls, max_tool_calls_per_step, max_identical_tool_calls, max_delegations, max_tokens_per_run, max_cost_usd_per_run). Each is held to the parent's value for that key.
  4. Choose Save runtime, and test from the parent's Playground.
Note

A sub-agent defined on the parent spends the parent's budget and cannot delegate further. A registered agent used as a sub-agent runs as itself, under its own guardrails, kill switch and budget, and its cost is billed on to the parent.

Each sub-agent's own limits

A sub-agent defined on the parent inherits the parent's context budget, reply cap, step cap and per-run limits unless you set its own. Each of the four fields above is optional and is stored only when set, so a sub-agent saved before the fields existed runs exactly as it did.

  • A value wider than the parent's is refused when you save, with a message that names the sub-agent and the field. A sub-agent cannot widen what the parent is held to.
  • Its own run limits are nested inside the parent's. What the sub-agent spends still counts toward the parent's totals, so the parent's caps are checked on every call the sub-agent makes. When the sub-agent reaches one of its own limits, only that delegation ends. The parent is told why and carries on. When the parent's limit is reached inside a delegation, the whole run ends, as before.
  • Its context budget is held to the window of the model it runs on, which may differ from the parent's when it has a model override.

GET /api/agents/{key}/runtime returns an effective object with the values a run will actually use, for the parent (effective.agent) and for each sub-agent (effective.subagents.<name>): window_tokens (the model's input window from the catalogue, or null when it is not known), context_budget_tokens, max_tokens, max_iterations and limits. These are computed from the saved runtime and the model catalogue and are never stored. A registered agent used as a sub-agent is shown with its own agent's values.

How delegation is governed

  • Each delegation is checked by the Cedar delegate action. You can also run one directly with POST /api/agents/{parent}/delegate/{child}, under the parent's budget.
  • A sub-agent runs as its parent runs (Run as), so a per-user MCP server can be ticked for it only when the parent runs as the invoker.
  • A delegation that would loop back to an agent already working on the request, or exceed the parent's Delegation depth (default 3, at most 5), is refused.
  • Cost is billed to the real parent, and every usage row carries the delegation chain, so you can see which parent a sub-agent's spend belongs to.

Next steps