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Decision infrastructure

Where decisions live.

TypeFuse is where the decisions AI makes for your business are built, tested and shipped.

Connect your agent

Decision infrastructure

Make your first decision answerable.

Every decisionbuilttestedon record

Connect your agent

Your agents make decisions, and nobody can answer for them. TypeFuse makes every decision answerable. Your agent connects to TypeFuse, writes a Decision with worked examples and tests, and asks to ship it. A person approves the release. Your apps call it and get typed answers, and every call is recorded and sealed, ready to hand over as an evidence pack.

Tested
Evals against your real cases
Shipped
Approved, versioned, traceable
Decided· your model
TypeSafe Jev, the latest, with OpenAI GPT-6 Luna, Cloudflare Clef and Microsoft Decision-1 soon
Recorded
Every call and answer, sealed

Your agents make decisions, and nobody can answer for them. Who changed it? Was it tested? Why did it say yes? TypeFuse makes every decision answerable.

Connect your agent. One line installs TypeFuse in your agent, then you sign in and choose your organisation.

Ask for a decision. Your agent writes the contract, adds worked examples and tests it: 24 of 24 passed.

You approve, and it ships: a pinned release with a semantic version. Your agent asks; a second person approves.

Every call gets a typed answer. Your apps call the live release; TypeFuse validates the input, decides and records the run.

Every answer is on record: the input, release, model and answer of every call, sealed, ready to hand over as an evidence pack.

Make your first decision answerable.

Every decisionbuilttestedon record

How it works

01 · Build

Define it once

Write down the question, the facts it needs and the rules to follow. It's kept as YAML or JSON, beside your code.

acme/refunds.yamljev-1.13.0
  1. state_schemaTyped inputorder_total · days_since_delivery · reason
  2. contextPolicyRefund within 30 days of delivery…
  3. questionsNative answerseligible: noul · route: choice
02 · Test

Prove it on real cases

Real cases you confirm become tests, and every release is checked against them.

42 of 42 confirmed cases match, release 1.4.0

  • Damaged on arrival, day 12approve
  • Changed mind, day 41decline
  • Partial refund requestedreview
03 · Ship

Ship it, then keep watch

Compatible changes reach your app on their own; a breaking one waits for you. Every call is measured.

  1. 1.3.2Was live; your app accepts ^1.2.0
  2. 1.4.0LiveCompatible: picked up on its own
  3. 2.0.0WaitsNew contract: waits until you choose it
MonitorLast 14 days
calls
10,790
typical
410 ms
approve
71%

How it works

From first draft to live, in one place.

Build the Decision, test it on real cases, then ship it to your application. Every step is kept, so you can see how any answer came to be.

TypeFuse is where your AI decisions are built, tested and shipped.

  1. 01 · Build

    Define it once

    Write down the question, the facts it needs and the rules it should follow, once. It is kept as YAML or JSON, so it can sit alongside your code.

    acme/refunds.yamlformat: 3 · model: jev-1.13.0Example
    1. state_schemaTyped inputJSON Schema for what callers send. Invalid input is refused before the model is asked.order_total: number · days_since_delivery: integer · reason: string
    2. contextPolicyStatic rules and reference material, versioned with the decision.policy: Refund within 30 days of delivery…
    3. questionsNative answersQuestions in TypeSafe's own types: a noul for yes or no, a choice for one of a set, a score for a level on a scale.eligible: noul · route: choice (approve, review, decline)
  2. 02 · Test

    Prove it on real cases

    Worked examples show anyone what you meant. Real cases you confirm become tests, and an evaluation compares recorded answers, so it always gives the same result.

    Core test setExampleEvaluated against release 1.4.0

    42 of 42 confirmed cases matched

    • Damaged on arrival, day 12Expected approve, returned approve, matched
    • Changed mind, day 41Expected decline, returned decline, matched
    • Partial refund requestedExpected review, returned review, matched

    Repeatable: an Evaluation compares the answers a Test run recorded, so reading it again gives the same result.

  3. 03 · Ship

    Ship it, then keep watch

    Publishing freezes a version you can always return to. Your application picks up compatible changes on its own; a breaking change waits until you choose it. Once it's live, every call is measured and on record.

    Releasesacme/refundsExample

    Release lines for acme/refunds.

    1. 1.0.0, first release: the first input and answer contract.
    2. 1.3.0, behaviour change: added the route question.
    3. 1.3.2, patch: clarified the review criteria.
    4. 1.4.0, behaviour change: damaged goods always qualify. Live in production.
    5. 2.0.0, major release with a new contract: a new required input field. It starts the 2.x line.

    Your application accepts ^1.2.0, meaning 1.2.0 or later and below 2.0.0, so it is served 1.4.0.

    Callers accepting ^1.2.0 get 1.4.0. The new contract in 2.0.0 waits on its own major line until they opt in.
    MonitorLast 14 days
    10,790calls · 410 ms typical
    approve 71%review 22%decline 7%approve up 9 points on last week
    AuditIntact
    10,790 of 10,790 calls sealed

    Every call keeps its input, release and answers. Download an evidence pack for any period.

    See the audit trail

Start in your agent

Build your first Decision from Claude or Codex.

Your agent does the building. It writes the Definition, adds Examples and tests it, and checks with you before it publishes.

  1. 1

    Install

    One command adds the TypeFuse skill and tools to your agent.

    In your terminal
    curl -fsSL https://typefuse.dev/install | sh
    Read the setup guide for each agent
  2. 2

    Sign in

    Choose the organisation your agent works in.

    Connected toacme
  3. 3

    Ask for a Decision

    Describe it in your own words. Your agent takes it from there.

    Ask your agent
    Build a Decision that checks whether a refund request is eligible and routes it to approve, review or decline.

Prefer to work on screen?The workbench is in the app

Prefer to work on screen?Build it in the workbench

The workbench

Or build it in the workbench.

Write the Definition on screen, with the assistant suggesting fixes as you go. Then test it and ship it from the same page, which always shows the next step.

An example Decision, acme/refunds, taken from a draft change to a live release. Build: the route question's instructions are written, and the draft compiles. Assistant: the assistant review finds that escalate doesn't say what to do with partial refunds, suggests a fix and the fix is accepted into the draft. Test: the Core test set runs, and all 42 confirmed cases match. Ship: 1.4.0 is published and goes live in production.

Audit

Every outcome, traced.

When someone asks why a decision went the way it did, the answer is already recorded, and nothing can be quietly rewritten.

Why did it answer that?Intact
Input
Damaged on arrival, day 12
Release
1.4.0 · accepts ^1.2.0
Model
jev-1.13.0
Answer
route: approve 0.91
Sealed
chain head 9f2c 71be

An evidence pack covers any period for a review, with the proof that nothing in it has changed.

Audit

Every outcome, traced.

When someone asks why a decision went the way it did, the answer is already recorded. It is there for your compliance team, for an auditor checking your controls and for the customer asking why their refund was declined.

Every call keeps
  • The input your application sent, checked against the Decision's schema
  • The release that answered it, and the exact model version
  • Every answer, with its probabilities
  • When it was asked, and which application asked
Every release keeps
  • The Test set it was evaluated against, and the result
  • Who approved it, when your organisation asks for a second person
  • What changed since the release before it

Nothing can be quietly rewritten. Calls and changes are sealed into a chain within a minute of being recorded, so anyone can check the record is intact.

For a review, download an evidence pack for any period: a summary of every release that was live, how it was tested, who approved it and the calls it answered, with the records themselves and the proof that none of them has changed.

Why did it answer that?Example
  1. Call: run_01J9Q4, production. one record for every call
  2. Decision: acme/refunds. identified by organisation and name
  3. Release: 1.4.0, Behaviour, accepts ^1.2.0. the exact contract the caller accepted
  4. Plan: 4c1e 9a02, compiled from the Definition. what the model was actually asked
  5. Input: sha256 9f2c 71be, stored with the run. replayable, byte for byte
  6. Evidence: Core test set, 42 of 42 matched. what this release was measured against
  7. Answer: route chose approve, probability 0.88. what the caller received

Answered in 412 ms, with its record kept for audit.

Evidence packA PDF summary, the records and their proof, in one zip.Sample
TypeFuseEvidence pack
Refundsacme/refunds · release 1.4.0Evidence for 1–30 September 2026Generated 1 October 2026 at 09:30 UTC

Prepared for Acme by Sarah Mitchell.

Calls
3,184
Releases live
2
Sealed
100%
In this pack
  • summary.pdfThis summary
  • calls.csvEvery call, with its release and answers
  • changes.csvEvery change to the Decision
  • evaluations.jsonTest runs and their results
  • seals.jsonThe proof the records are unchanged
Evidence pack · acme/refunds · 1–30 September 2026

Releases live in this period

1.4.0 r12 · production · Live from 2 SeptemberApproved by James Carter, 2 September 2026 at 10:12 UTC

Evaluations and calibration

Core test set · cases agreeing 42 of 42 (100%)

Approvals

Deploy 1.4.0 r12 to production: asked by Sarah Mitchell, approved by James Carter

Calls

The Decision answered 3,184 calls in this period, 2 of which failed.1.4.0 · 3,071 calls · 1.3.2 · 113 calls

Proof that these records have not changed

Sealed calls 3,184 of 3,184 · 1,906 sealsIntactchain head 9f2c71be…4c1e
TypeFuse · acme/refundsPage 2 of 6

Private preview

Own your next decision.

Put the decisions AI makes for your business under your control, with a record you can stand behind.

Join the preview Sign in
  • Your criteriaThe people who own a decision set its rules, and change them when the business changes.The people who own a decision set its rules.
  • Your evidenceEvery release is tested against real cases before your application ever sees it.Every release is tested on real cases first.
  • Your recordEvery answer is traced and sealed, ready for an auditor or the customer who asks why.Every answer is traced and sealed.