Head to head · Tax calculate · October 2026 research run
Quaderno vs Zamp
Quaderno scores 59.5 (C) on agent readiness against Zamp's 49.5 (D), and leads in 4 of 7 scored categories. Zamp leads on agent ergonomics and maintenance & community. Both do tax calculate.
Which one, for what
Quaderno C
Good for An agent working for a SaaS, digital-goods or e-commerce seller that needs a tax rate at checkout, a record of each sale with location evidence, and compliant invoices, including Spanish Verifactu and TicketBAI.
Ahead on
- Reliability, 91 against 72
- Schema & documentation, 77 against 44
- Payments & pricing, 30 against 20
- Transparency & trust, 76 against 50
Watch for
One API key reads and writes everything its user can reach. Scopes exist only on Connect OAuth tokens (read_only, read_write)
Zamp D
Good for An agent working for a US or Canadian seller that wants Zamp's team to register, file and remit, and needs calculation and transaction sync through a small API.
Ahead on
- Agent ergonomics, 64 against 56
- Maintenance & community, 42 against 28
Also in its favour
- Free to start without a card
Watch for
No OpenAPI file for the API. The one file on the docs host is the documentation platform's plant store sample
Score by category
| Category | Weight this run | Quaderno | Zamp | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 91 | 72 | Quaderno +19 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 77 | 44 | Quaderno +33 |
| Agent ergonomics | 13%16.2 | 56 | 64 | Zamp +8 |
| Security & auth | 14%17.5 | 39 | 40 | Zamp +1 |
| Payments & pricing | 10%12.5 | 30 | 20 | Quaderno +10 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 28 | 42 | Zamp +14 |
| Transparency & trust | 7%8.8 | 76 | 50 | Quaderno +26 |
| Negative events | ≤15 | 0 | 0 | |
| Total | 59.5 · C | 49.5 · D |
Facts side by side
| Fact | Quaderno | Zamp |
|---|---|---|
| Kind | HTTP API | HTTP API |
| Vendor | Recrea Systems, SL | Zamp Inc. |
| Hosted endpoint | https://quadernoapp.com/api | https://api.zamp.com |
| Transports | HTTP | HTTP |
| Auth | OAuth or key | API key |
| Pricing | Paid | Paid |
| x402 | no | no |
| Licence | Proprietary service under Quaderno's terms of service. The Ruby library on GitHub is MIT | Proprietary service under Zamp's Standard Terms and Conditions, which form part of a signed Order Form. The sandbox has its own Developer trial terms |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-07-04 | 2026-08-31 |
| Terms last updated | 2026-09-15 | no date given |
| Privacy policy last updated | 2024-05-16 | 2025-02-11 |
| Customer content may train models | not found in the text | not found in the text |
| Terms restrict automated access | yes | yes |
| Terms restrict benchmarking | yes | yes |
| Terms or service can change without notice | yes | not found in the text |
| Arbitration or class-action waiver | not found in the text | not found in the text |
| Popularity | 15 stars | none |
Verdicts
Quaderno
A public OpenAPI 3.1 spec covers 92 operations, with a free sandbox and a status page showing no incident since July 2025. The API key has full account access, there are no idempotency keys, and the newest public API version is dated October 2024.
Zamp
A free 30-day sandbox key needs no card or sales call, and the docs are served as Markdown with llms.txt and a published limit of 1,000 requests a minute. There is no OpenAPI file, SDK, API changelog or published price, production keys come with a sales-led account, and the site footer says SOC 2 compliance is in progress.
Before you call either
Quaderno
- Call GET https://quadernoapp.com/api/authorization first. Its
hrefgives the account subdomain that every other call needs - Before retrying a failed POST /transactions, list invoices by
processor_idto check whether the sale was recorded. There is no idempotency key - Treat GET /invoices/{id}/deliver as a write. It emails the invoice to the customer
- Correct a final invoice with a credit note. DELETE on invoices returns 410 and PUT accepts only notes, tags, metadata and address fields
- Read X-RateLimit-Remaining and X-RateLimit-Reset, and page with
created_beforeandlimitup to 100
Zamp
- Call
POST /calculationsfor a quote andPOST /transactionsonly when the sale is final. Put the returnedtaxDueintaxCollectedwhen posting - Keep transaction and line item ids to 25 characters. A repeated
POST /transactionswith an existing id returns 409CONFLICT, so a retry doesn't create a second record - For a refund, post a new transaction with
parentIdset to the sale's id and a negativequantity. Never send a negativeamounton a line item - Send
shipToAddress.stateandcountryset to CA for Canadian orders.POST /addressesvalidates US addresses only - Page lists with
limit(1 to 100, default 10) andcursoruntilnextCursoris null.GET /transactionsreturns only transactions written with the same key - Don't store sensitive or personal data in the sandbox. Trial data is deleted after 30 days and the trial terms forbid live customer data
Questions
Which is better for AI agents, Quaderno or Zamp?
Quaderno scores 59.5 (C) on agent readiness against Zamp's 49.5 (D), and leads in 4 of 7 scored categories. Zamp leads on agent ergonomics and maintenance & community.
Do Quaderno and Zamp need an API key?
Quaderno takes an API key or an OAuth sign-in. Zamp needs an API key.
Can an agent call Quaderno and Zamp without installing anything?
Yes. Quaderno has a hosted endpoint at https://quadernoapp.com/api and Zamp at https://api.zamp.com.
Other comparisons with Quaderno or Zamp
Machine-readable
- This page as Markdown
/compare/quaderno-vs-zamp.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/quaderno.json·/api/v1/tools/zamp.json - From a terminal
anchor compare quaderno zamp(the CLI) - Over MCP
compare_tools {"a": "quaderno", "b": "zamp"}at/mcp, no key