# Metronome vs Orb

> Metronome scores 69.7 (B) to Orb's 66.5 (B) for usage billing. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/metronome-vs-orb
- Markdown: https://www.anchorterminal.com/compare/metronome-vs-orb.md (~2,250 tokens)
- Slim: https://www.anchorterminal.com/compare/metronome-vs-orb.min.md (~630 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/metronome-vs-orb.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-09

Metronome scores 69.7 (B) on agent readiness against Orb's 66.5 (B), and leads in 2 of 7 scored categories. Orb leads on reliability and agent ergonomics. Both do usage billing.

- Metronome: grade B, 69.7/100, rank #173 of 950. Markdown https://www.anchorterminal.com/tools/metronome.md · JSON https://www.anchorterminal.com/api/v1/tools/metronome.json
- Orb: grade B, 66.5/100, rank #289 of 950. Markdown https://www.anchorterminal.com/tools/orb.md · JSON https://www.anchorterminal.com/api/v1/tools/orb.json
- Best payment and monetisation platforms for AI agents: https://www.anchorterminal.com/best/payment-platforms/index.md
- All 76 platforms comparisons: https://www.anchorterminal.com/compare/payment-platforms/index.md

## Which one, for what

### Metronome (B)

Good for: A company that meters usage and bills on contracts, credits and commits, with invoices delivered through Stripe, NetSuite or cloud marketplaces.

Ahead on:
- Security & auth, 68 against 55
- Payments & pricing, 39 against 5

Watch for: Errors are a single `message` string with no machine-readable code, and the API description documents a 4xx response on 87 of 142 operations

### Orb (B)

Good for: A software or AI company that bills on usage and needs event metering, plan versioning, prepaid credits, invoicing and revenue reporting behind one API, with Stripe or Adyen collecting the money.

Ahead on:
- Reliability, 77 against 68
- Agent ergonomics, 84 against 75

Watch for: All three plans (Core, Advanced, Enterprise) show custom pricing only, and the pricing page sends new customers to sales


## Score by category

| Category | Weight | Metronome | Orb | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 68 | 77 | Orb +9 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 88 | 88 | even |
| Agent ergonomics | 13% (16.2 this run) | 75 | 84 | Orb +9 |
| Security & auth | 14% (17.5 this run) | 68 | 55 | Metronome +13 |
| Payments & pricing | 10% (12.5 this run) | 39 | 5 | Metronome +34 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 82 | 82 | even |
| Transparency & trust | 7% (8.8 this run) | 65 | 65 | even |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **69.7 · B** | **66.5 · B** | |

## Facts side by side

| Fact | Metronome | Orb |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Metronome (Stripe) | Orb, Inc. |
| Hosted endpoint | `https://api.metronome.com` | `https://api.withorb.com/v1` |
| Transports | HTTP | HTTP |
| Auth | API key | API key |
| Pricing | Pay per use | Paid |
| x402 | no | no |
| Licence | Proprietary service under the Stripe Services Agreement. The SDKs on GitHub are Apache-2.0 | Proprietary service under Orb's Platform Terms and Conditions. The SDKs on GitHub are Apache-2.0 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-09-29 | 2026-10-09 |
| Terms last updated | 2026-09-28 | 2024-11-13 |
| Privacy policy last updated | 2026-04-28 | 2025-05-07 |
| Customer content may train models | yes | not found in the text |
| Terms restrict automated access | not found in the text | not found in the text |
| Terms restrict benchmarking | not found in the text | not found in the text |
| Terms or service can change without notice | yes | not found in the text |
| Arbitration or class-action waiver | yes | not found in the text |
| Popularity | 7 stars, 363k npm/wk | 5 stars, 185k npm/wk |

## Verdicts

**Metronome.** Metronome's API carries an `Idempotency-Key` on every POST, a public OpenAPI description of 142 operations, and agentic tokens whose writes wait for a person's approval. Prices for the Startup plan are public. Errors return only a `message` string, token scopes are set through support, and the status feed lists 13 incidents since 22 July 2026.

**Orb.** Orb suits a company that bills on usage and wants one API for events, plans, credits and invoices. It publishes an OpenAPI 3.1 file, numeric rate limits, idempotency keys and a dry-run header. Every plan is priced on request and access starts with sales. No scope list for API keys or public sub-processor list was found.

## Before you call either

### Metronome

1. Send an `Idempotency-Key` header on every POST and reuse it on retry. A cached error is returned for the same key, so use a new key after fixing the cause
2. Give each usage event a stable `transaction_id`. Metronome ignores repeats for 34 days and accepts at most 100 events per `/v1/ingest` call
3. On 429 read `X-Metronome-Rate-Limit-Type` (`client` or `customer`) and back off. Unlisted endpoints default to 8 requests a second
4. With an agentic token, expect `403 AgenticMutationBlocked` on writes. Post the original method, path and body to `/v1/approval_requests` and show the person the `approval_url`
5. Use a sandbox token for testing. The token alone decides whether a call reaches sandbox or production data

### Orb

1. Call `https://api.withorb.com/v1` with `Authorization: Bearer <key>`. A person creates the key in the Orb web app under organisation settings, in test mode or live mode
2. Send an `Idempotency-Key` of at most 64 characters on every POST and PATCH. A 409 means the first request is still running or the body changed
3. Add `Dry-Run: True` to check a write first, and confirm `Orb-Dry-Run: true` in the response. Ingest, amend and deprecate event calls ignore it and run for real
4. Do not send `Idempotency-Key` with `Dry-Run`. Orb returns a validation error
5. Page with `limit` (default 20, maximum 100) and pass `next_cursor` back as `cursor` while `has_more` is true
6. Back off exponentially on 429. Test mode allows 5 writes a second and 2,000 ingested events a minute

## Questions

### Which is better for AI agents, Metronome or Orb?

Metronome scores 69.7 (B) on agent readiness against Orb's 66.5 (B), and leads in 2 of 7 scored categories. Orb leads on reliability and agent ergonomics.

### Do Metronome and Orb need an API key?

Both need an API key.

### Can an agent call Metronome and Orb without installing anything?

Yes. Metronome has a hosted endpoint at https://api.metronome.com and Orb at https://api.withorb.com/v1.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/metronome-vs-orb.json, and with the fewest tokens: https://www.anchorterminal.com/compare/metronome-vs-orb.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "metronome", "b": "orb"}`. From a terminal: `anchor compare metronome orb`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/metronome.json and https://www.anchorterminal.com/api/v1/tools/orb.json

## Other comparisons with Metronome or Orb

- [ATXP vs Metronome](https://www.anchorterminal.com/compare/atxp-vs-metronome.md)
- [ATXP vs Orb](https://www.anchorterminal.com/compare/atxp-vs-orb.md)
- [Lago vs Metronome](https://www.anchorterminal.com/compare/lago-vs-metronome.md)
- [Lago vs Orb](https://www.anchorterminal.com/compare/lago-vs-orb.md)
- [Metronome vs Nevermined API + MCP](https://www.anchorterminal.com/compare/metronome-vs-nevermined.md)
- [Metronome vs Paid](https://www.anchorterminal.com/compare/metronome-vs-paid.md)
- [Metronome vs Stripe API + MCP](https://www.anchorterminal.com/compare/metronome-vs-stripe-mcp.md)
- [Metronome vs Tempo](https://www.anchorterminal.com/compare/metronome-vs-tempo.md)
- [Nevermined API + MCP vs Orb](https://www.anchorterminal.com/compare/nevermined-vs-orb.md)
- [Orb vs Paid](https://www.anchorterminal.com/compare/orb-vs-paid.md)
- [Orb vs Stripe API + MCP](https://www.anchorterminal.com/compare/orb-vs-stripe-mcp.md)
- [Orb vs Tempo](https://www.anchorterminal.com/compare/orb-vs-tempo.md)
- [Adyen MCP server vs Orb](https://www.anchorterminal.com/compare/adyen-mcp-server-vs-orb.md)
- [Crossmint API + Docs MCP vs Orb](https://www.anchorterminal.com/compare/crossmint-vs-orb.md)
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- [Orb vs Skyfire API + MCP](https://www.anchorterminal.com/compare/orb-vs-skyfire.md)
- [Metronome vs PayPal MCP server](https://www.anchorterminal.com/compare/metronome-vs-paypal-mcp-server.md)