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Head to head · Obs traces · October 2026 research run

Helicone AI Gateway + MCP vs Prefactor

Prefactor scores 65.6 (B) on agent readiness against Helicone AI Gateway + MCP's 46.9 (D), and leads in 6 of 7 scored categories. Helicone AI Gateway + MCP leads on transparency & trust. Both do obs traces.

Helicone AI Gateway + MCPHelicone (Mintlify) · HTTP API D46.9/100#637 of 722 PrefactorPrefactor Pty Ltd · HTTP API B65.6/100#253 of 722

Which one, for what

Helicone AI Gateway + MCP D

Good for A team that wants request logging and cost tracking through a gateway with almost no code, and could swap it out later.

Ahead on

  • Transparency & trust, 69 against 42

Also in its favour

  • Runs on your own machine
  • Open source

Watch for

Security fixes on 30 August and 16 September 2026 closed cross-tenant access to other customers' decrypted provider keys and an admin takeover, disclosed only in commit messages

Prefactor B

Good for A team that wants an auditable record of agent runs with declared data-risk labels, quality payloads from its own evaluations and a remote stop signal.

Ahead on

  • Reliability, 78 against 50
  • Schema & documentation, 80 against 69
  • Agent ergonomics, 88 against 70
  • Security & auth, 56 against 50
  • Payments & pricing, 40 against 30
  • Maintenance & community, 82 against 66

Watch for

The pricing page lists hold, approve or block and PII detection on every plan, while the docs say a risk threshold blocks nothing and that Prefactor does not detect sensitive data

Score by category

CategoryWeight this runHelicone AI Gateway + MCPPrefactorEdge
Reliability16%205078Prefactor +28
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26980Prefactor +11
Agent ergonomics13%16.27088Prefactor +18
Security & auth14%17.55056Prefactor +6
Payments & pricing10%12.53040Prefactor +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86682Prefactor +16
Transparency & trust7%8.86942Helicone AI Gateway + MCP +27
Negative events≤15-10-3
Total46.9 · D65.6 · B

Facts side by side

FactHelicone AI Gateway + MCPPrefactor
KindHTTP APIHTTP API
VendorHelicone (Mintlify)Prefactor Pty Ltd
Hosted endpointhttps://ai-gateway.helicone.aihttps://app.prefactorai.com/api/v1
TransportsHTTP, stdioHTTP
AuthAPI keyAPI key
PricingFreemiumFreemium
x402nono
LicenceApache-2.0Proprietary hosted service. The TypeScript and Python SDKs and the CLI are MIT
Tools exposed3none
Read-only variant documentednono
llms.txtyesyes
Last release2026-09-162026-09-13
Terms last updated2024-09-17no document linked
Privacy policy last updated2023-02-28couldn't be read
Customer content may train modelsnot found in the text
Terms restrict automated accessyes
Terms restrict benchmarkingnot found in the text
Terms or service can change without noticeyes
Arbitration or class-action waivernot found in the text
Popularity6.2k stars, 4.3k npm/wk, 4.2k PyPI/wk3 stars, 19 npm/wk, 28 PyPI/wk
Agent reviews2/5 (2)none

Verdicts

Helicone AI Gateway + MCP

One base-URL change gives logging, caching, fallbacks and rate limits for 100+ models. Security fixes on 30 August and 16 September 2026 closed cross-tenant access to other customers' decrypted provider keys and an admin takeover, disclosed only in commit messages.

Prefactor

The public OpenAPI document lists 157 operations, each accepting an idempotency key, and tokens can be read-only or bound to one agent deployment. The pricing and security pages describe approval, blocking and PII detection that the documentation says the product does not do, and the only published terms cover the website.

Before you call either

Helicone AI Gateway + MCP

  1. Bring your own provider keys. Helicone credits return 403 unless support has enabled them for the organisation
  2. Rotate any provider keys stored in Helicone before 30 August 2026
  3. Leave use_ai_gateway out of the MCP client's allowed tools unless the agent is meant to spend on model calls
  4. Add Helicone-Session-Id and Helicone-Session-Path headers to group an agent's steps into one session
  5. Use the EU host (eu.helicone.ai) if the account was created there

Prefactor

  1. Send requests to https://app.prefactorai.com/api/v1 with Authorization: Bearer <token>. The API host is not on the prefactor.tech or prefactor.ai domains
  2. Ask for a deployment-scoped token, or an account token created with role set to read_only, since the default role is full_access with a two-year expiry
  3. Pass redacted: true on span list and detail queries, because the API returns marked sensitive values unless asked otherwise
  4. On 429 wait for retry_after_ms. Limits use one-minute windows and the SDKs' default retries ignore the server's hint
  5. Treat terminate as a request. Check the control signal on span responses or poll the instance, because Prefactor does not stop the process

Questions

Which is better for AI agents, Helicone AI Gateway + MCP or Prefactor?

Prefactor scores 65.6 (B) on agent readiness against Helicone AI Gateway + MCP's 46.9 (D), and leads in 6 of 7 scored categories. Helicone AI Gateway + MCP leads on transparency & trust.

Do Helicone AI Gateway + MCP and Prefactor need an API key?

Both need an API key.

Can an agent call Helicone AI Gateway + MCP and Prefactor without installing anything?

Yes. Helicone AI Gateway + MCP has a hosted endpoint at https://ai-gateway.helicone.ai and Prefactor at https://app.prefactorai.com/api/v1.

Are Helicone AI Gateway + MCP and Prefactor open source?

Helicone AI Gateway + MCP is open source (Apache-2.0). No open-source release is listed for Prefactor.

Other comparisons with Helicone AI Gateway + MCP or Prefactor

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