Multi-agent
Several agents on one job — rarely worth the 15x token bill.
Multi-agent is the difference between one AI doing your job and a lead agent farming pieces out to specialists. It genuinely wins on read-heavy parallel work — 40 supplier pages, 300 CVs — where subtasks are independent and read-only. Everywhere else it multiplies token cost and failure surface, and one well-instrumented agent beats the swarm.
You need this when
- You run read-heavy parallel research: dozens of sites, CVs or suppliers checked at the same time, independently.
- Your roles need different tools or permissions — e.g. a voice agent that hands off to the only agent allowed to write to the calendar.
- One job's context genuinely exceeds a single window, and the pieces can be summarised back without losing decisions.
You can skip it when
- Your workflow is sequential and each step depends on the last — use one agent with good tools and a checklist prompt instead.
- The task is writing or coding, where subagents make invisible conflicting decisions — use one agent plus a human review gate instead.
- You just want it to look sophisticated in a demo — spend the money on logging, evals and a retry policy for your single agent instead.
The long version
What it is — in one coffee-break
Multi-agent means more than one AI agent on the same job: a lead agent splits the task, hands pieces to specialists, and stitches the results back. Three shapes turn up: handoff (support agent passes the ticket to billing), delegation (an orchestrator spawns four researchers, merges findings), debate (two argue, a third judges). The test is blunt: does the product genuinely support agents working together, or does it call one model repeatedly and print the steps with job titles on?
This sits in the Emerging row, and Emerging means unsettled. Anthropic found a lead-plus-subagents setup beat a single agent by 90.2% on their internal research eval — while burning roughly 15x the tokens of a chat, with token usage alone explaining 80% of the performance variance. Much of the "multi-agent is smarter" effect is simply "we spent 15x more".
When you actually need it (and when you don't)
Handoffs genuinely help in two places. First, read-heavy parallel work: 40 supplier price pages, 300 CVs, a dozen competitor sites. The subtasks are independent, read-only, and each fits its own context window, so nothing collides. Second, role separation where roles carry different tools and permissions — a voice agent that answers, then hands the caller to the one agent allowed to write to your calendar. That buys a permission boundary, not brains.
Theatre: anything sequential, anything with shared evolving state, and most writing and coding work. Cognition put it bluntly in Don't Build Multi-Agents: parallel subagents make implicit decisions the others cannot see, so one built a Super Mario background for the Flappy Bird clone another was drawing. The MAST taxonomy points the same way: 14 distinct failure modes across seven popular frameworks, mostly coordination failures rather than model failures.
Default for a small business: one well-instrumented agent with good tools and full logs. Add a second only when you can name the subtask, prove it is read-only, and show it runs alongside its siblings, not after.
How to recognize good vs bad implementations
Good implementations expose the seams: you see which agent ran, what it was told, what it returned, and what the orchestrator did with it. Bad ones show an animated list of role names — Researcher, Analyst, Writer — over one prompt chain in costume.
Three questions that end a sales demo quickly. Show me the trace: which agent produced this sentence, and what did it cost in tokens? No per-agent trace and no per-agent token count means you can neither debug nor budget it. What happens when subagent three returns garbage — retry, drop, or pass through? That should be a named policy, not a shrug. Can two agents run at once, or is this a queue? A queue means you pay multi-agent prices for sequential work.
One more tell: good products cap subagent count and token budget per run, and treat human escalation as a first-class handoff.
What this costs
At July 2026 rates — Claude Sonnet 5 at $2 per million input tokens and $10 output, Opus 5 at $5 and $25 — a single-agent research brief using 80k input and 10k output costs about $0.26 (EUR 0.24). The same brief as an Opus orchestrator with four Sonnet subagents, at the measured 15x multiplier, lands near $4 to $6 (EUR 3.70 to EUR 5.50). Two hundred briefs a month: EUR 48 against EUR 800 to EUR 1,100. That gap must buy something you can name.
Hosted orchestration adds a layer. CrewAI's cloud free tier allows 50 executions a month; Professional is $25 a month for 100 executions and two users, and you still bring your own LLM keys. Published per-run figures for a three-agent crew: $0.06 to $0.12 on GPT-4o-mini, $0.10 to $0.20 on GPT-4o, and $1.50 to $12 per hour in sustained production.
The self-hosted path is cheap on licence: CrewAI, LangGraph and the OpenAI Agents SDK are open source, and a VPS runs EUR 5 to EUR 20 a month. You do not escape tokens — over 90% of the bill, and self-hosting does not shrink them. Open-weight models on a EUR 1,500 to EUR 2,500 workstation delete the token line, but small models coordinate badly — the exact thing you were buying.
Where to see it scored
We audited 62 tools; 37 carry a score here. Top: Genspark (9) and Gemini / Google (9), both running genuine parallel subagents with visible per-agent output. Vapi (8) scores on voice handoffs between agents holding different tools; Claude / Anthropic (8) on subagent delegation with per-agent context isolation. The bottom is where the marketing lives: Cognism (2.5) and Base44 (2) use agent language for one model on a chain. Read Anthropic's numbers against Cognition's counter-argument: they disagree, and both are right about different tasks.
Flashcards
Check yourself
1. Anthropic's multi-agent research system used roughly how many times the tokens of a chat?
2. Which task is the best genuine fit for multi-agent?
3. What did the MAST taxonomy find most multi-agent failures were?
4. Which question best exposes fake multi-agent in a demo?
5. At July 2026 Claude rates, what does a 200-brief month cost multi-agent vs single-agent?
Cheat sheet
- Handoff, delegation, debate — three shapes; only handoff is usually worth it.
- Anthropic: 15x tokens vs chat; token spend alone explains 80% of the gain.
- MAST: 14 failure modes across 7 frameworks — coordination, not the model.
- Parallel + read-only + independent = good. Sequential + shared state = theatre.
- Demand per-agent traces and per-agent token counts, or you cannot budget it.
- EUR 0.24 per brief single-agent vs EUR 3.70-5.50 multi-agent. Name the payoff.
Who actually does this well
| Best on this element | Score | Why it scored that |
|---|---|---|
| Gemini / Google | 9 | Google authored the A2A protocol (50+ partners), Agent Engine runs A2A agents in production, and ADK/Antigravity ship multi-agent orchestration with subagents. |
| Genspark | 9 | A dedicated Multi-Agent Platform: a lead agent coordinates multiple specialized sub-agents in parallel with shared context, and can spin up new ephemeral agents defined by their ow |
| Claude / Anthropic | 8 | Subagents in the Agent SDK and Claude Code plus multi-agent orchestration in Managed Agents; functional and shipping, slightly younger than the single-agent surface. |
| Vapi | 8 | Squads let specialized assistants hand off mid-call with controlled context passing; one customer (Fleetworks) runs 240,000 calls/day through the feature in production. |
| Glean | 7.5 | A named 'Agent Orchestration' surface: agents trigger other agents on schedule, route queries to specialists, and the headless builder supports sub-agents as a composition primitiv |
| Microsoft 365 Copilot | 7.5 | Critique and Council run multiple models together, Copilot Studio and the Agent Framework orchestrate multi-agent systems, and Agent 365 already manages tens of millions of agents. |
| Windsurf (Devin Desktop) | 7.5 | Devin Local spawns subagents for subtasks, parallel sessions run concurrently on isolated worktrees, and cloud delegation to 'a team of Devins' with PR review in-editor is the flag |
| ChatGPT / OpenAI Platform | 7 | Handoffs and multi-agent patterns supported in the Agents SDK; young but functional. |
And the other end of the same column:
| Weakest | Score | Why it scored that |
|---|---|---|
| Bolt (Bolt.new) | 3 | No native multi-agent orchestration; Bolt is a single-agent system. MCP connectors could theoretically chain tools but there is no agent-to-agent coordination, debate, or delegatio |
| Higgsfield | 3 | "AI Employees" and Supercomputer are marketing language for a single orchestrator that routes across 30+ generation models -- not multiple specialized agents handing off or debatin |
| Cognism | 2.5 | No delegation, handoff or coordination between multiple agents is documented — each AI feature (search, research, persona builder) runs independently. |
| Base44 | 2 | Superagents run independently per workflow; there's no shipped feature for multiple agents coordinating, handing off, or debating on a shared task. |
Scored on 37 of 62 audited tools. Every score links to the full audit and its reasoning.