# Reynforce and agent-platform supervisors: Sierra and Decagon

**Sierra and Decagon check their own agents from the inside. Reynforce works
across every agent you run, on any platform, with one list of what's true
and one record of every promise.**

## The problem

> **Example: two agents, one buyer.** Your support agent runs on one
> platform. Your outbound agent runs on another. On Monday the support agent
> tells a customer that onboarding is free. On Wednesday the outbound agent
> quotes them a fee for it. Each platform's checks passed, because each saw
> only its own agent.

The buyer doesn't care which platform said what. They see one company.

## What Sierra and Decagon do

**Sierra** runs "supervisors" beside its agents. In Sierra's words,
"Supervisors run in parallel, reviewing each response as it's generated,
verifying facts, enforcing policy", stepping in or "escalating to a human
when needed." Monitors then review every conversation afterwards, including
"grounding in fact — do they stick to verified knowledge?"

**Decagon** uses Agent Operating Procedures. "An AOP is a step-by-step set of
natural language instructions backed by code." They're "the playbooks that
allow Decagon agents to resolve complex, multi-turn conversations reliably at
scale", "equipped with guardrails to keep sensitive operations safe".

Both are serious, well-built ways to keep a platform's own agent on track.

## What Reynforce does

1. **One list of what's true about your company**, shared by every agent.
   Every line has a named owner and the date someone last checked it.
2. **Rules for each agent.** What it may promise on its own, what needs a
   person first, and what it may never say.
3. **One record of every promise**, whichever platform the agent ran on.
   Kept so nobody can edit it.

> **Example: "Onboarding is free."** Both agents ask Reynforce before they
> say anything about onboarding. Both get the same answer, from the same
> line, owned by the same person. If that line changes, it changes for both.

## Side by side

| | Sierra and Decagon | Reynforce |
|---|---|---|
| Which agents it sees | The ones built on that platform | Every agent you run, on any platform |
| What it checks against | Knowledge and procedures set up in the platform | A list your own people own, line by line |
| Who owns the facts | Configuration inside the vendor's platform | Named people in your company |
| What you have afterwards | Flagged conversations and transcripts | A record of every promise, across all agents |

## Our view

**If your customer-facing agent runs on Sierra or Decagon, their checks are
a real strength.** Sierra's supervisors are the closest thing on an agent
platform to the check Reynforce makes.

Our view is that most companies won't end up with one agent on one platform.
They'll have a support agent, an outbound agent, maybe an agent their partner
runs, and their own people. A promise made by any of them lands on the same
buyer. That's why the list of what's true, and the record of what was
promised, should sit outside any one platform.

An agent on either platform could ask Reynforce before it promises a price, a
date or a feature, if the platform lets it call an outside tool.

> **The short version:** a platform's supervisor watches its own agent.
> Reynforce watches what your company promises, whichever agent said it.

## What it costs

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- **Do it yourself: £99 a month per agent.** You set it up; a second agent is a second seat.
- **Enterprise:** ten or more agents. We agree a price with you.
- **The 7-Day Agent Approval:** done for you, one-off — Complete £7,000 · Standard £4,500 · Starter £2,500. Approved in 30 days, or you don't pay — as long as you complete your part of the setup.

14-day free trial. No card is needed to start, and nothing is charged unless you add one.

[Start free trial](https://app.reynforce.com/signup) · [Book a call](mailto:callum@reynforce.com?subject=Reynforce%20%E2%80%94%20a%20call) · [Request your free audit](/free-audit.html)
<!-- costs:end — generated by website/build.py; do not hand-edit -->

## Sources

- [Sierra, confidence in every conversation](https://sierra.ai/blog/confidence-in-every-conversation),
  read 20 October 2026
- [Decagon, Agent Operating Procedures](https://decagon.ai/modules/aops),
  read 20 October 2026