Advisor

Advisor is a server tool: Routeplane runs it mid-generation instead of handing the call back to your client. When the calling model hits something it’s unsure about, it asks a stronger advisor model a self-contained question and gets back advice to act on — without delegating the whole task. Use it to let a fast, cheap main model escalate just the hard sub-questions to a stronger model.

Quick start

Enable the advisor by declaring advisor on the request tools array. The declaration pins the advisor model and instructions; at call time the model asks its question:

<Tabs items={[‘Responses API’, ‘Anthropic Messages’]}>

curl http://127.0.0.1:4356/v1/responses \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "anthropic/claude-haiku-4.5",
    "input": "Refactor this auth module. Ask the advisor before changing the token-rotation logic.",
    "tools": [
      {
        "type": "advisor",
        "model": "anthropic/claude-opus-4.8",
        "instructions": "You are a senior security engineer. Be precise about auth edge cases."
      }
    ]
  }'

curl http://127.0.0.1:4356/v1/messages \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "anthropic/claude-haiku-4.5",
    "max_tokens": 4096,
    "messages": [
      {"role": "user", "content": "Refactor this auth module. Ask the advisor before changing the token-rotation logic."}
    ],
    "tools": [
      {
        "type": "advisor",
        "name": "advisor",
        "model": "anthropic/claude-opus-4.8",
        "instructions": "You are a senior security engineer. Be precise about auth edge cases."
      }
    ]
  }'

**Protocol support.** The `advisor` declaration works on the **OpenAI Responses API** (`/v1/responses`) and the **Anthropic Messages API** (`/v1/messages`), which both carry server tools on the wire. The **Chat Completions** `tools` array only accepts `{type:"function"}` entries and cannot carry the declaration.

How it works

When the calling model invokes the tool, it supplies:

Argument	Description
prompt	A clear, self-contained question for the advisor.
model	Optional per-call override of the advisor model.

The advisor answers and its advice is returned to the calling model, which then continues the task. Unlike Sub-agent, the advisor doesn’t take over the work — it just answers a question.

Configuration

Declared on the tools-array entry:

Field	Type	Description
model	string	The advisor model. An absent value falls back to the per-call model arg, then the parent request model.
instructions	string	System instructions for the advisor.
tools	array	Provider server tools the advisor may use (e.g. web search), in provider-namespaced declaration form.

**Bounded by the server-tool loop.** An advisor turn runs inside a bounded loop — a default of 10 tool rounds, 30s per tool, and a 120s total budget per turn.

On Cloud

Advisor is enabled and managed on Routeplane Cloud, with per-run cost for the advisor calls visible in the request log. Self-hosters enable it with server_tools.advisor: true; it is then advertised per-request only when the caller declares it.

See also

• Sub-agent — delegate a self-contained task instead of asking a question
• Fusion — deliberate across a panel of models on one prompt
• Model variants — address a stronger variant of a model as the advisor