# Avalara AvaTax vs Kintsugi

> Avalara AvaTax scores 68.8 (B) on agent readiness against Kintsugi's 60.7 (C), and leads in 5 of 7 scored categories. Kintsugi leads on reliability. Both do tax calculate. Category scores, facts, verdicts and agent notes side by side.

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- 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: 2026-10-08

Avalara AvaTax scores 68.8 (B) on agent readiness against Kintsugi's 60.7 (C), and leads in 5 of 7 scored categories. Kintsugi leads on reliability. Both do tax calculate.

- Avalara AvaTax: grade B, 68.8/100, rank #172 of 722. Markdown https://www.anchorterminal.com/tools/avalara.md · JSON https://www.anchorterminal.com/api/v1/tools/avalara.json
- Kintsugi: grade C, 60.7/100, rank #392 of 722. Markdown https://www.anchorterminal.com/tools/kintsugi.md · JSON https://www.anchorterminal.com/api/v1/tools/kintsugi.json

## Which one, for what

### Avalara AvaTax (B)

Good for: An agent that must calculate and record US sales tax at address level, with VAT and GST in other countries, and hand the records to filing.

Ahead on:
- Agent ergonomics, 84 against 75
- Security & auth, 65 against 52
- Payments & pricing, 30 against 13
- Transparency & trust, 79 against 60

Also in its favour:
- No incidents deducted, where Kintsugi loses 3 points for them

Watch for: Production rate limits are not published. The only numbers found are the trial limits and 5 calls a minute on report exports

### Kintsugi (C)

Good for: An agent working for a seller that already has Kintsugi Premium and wants estimates, transaction sync, exemptions, nexus, registrations and filing status through one API, or read-only answers about an account through the OAuth MCP server.

Ahead on:
- Reliability, 73 against 62

Watch for: API access, SDKs and real-time tax calculation are listed only under Premium, which is priced on request. API keys need a paid plan that includes them


## Score by category

| Category | Weight | Avalara AvaTax | Kintsugi | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 62 | 73 | Kintsugi +11 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 85 | 87 | Kintsugi +2 |
| Agent ergonomics | 13% (16.2 this run) | 84 | 75 | Avalara AvaTax +9 |
| Security & auth | 14% (17.5 this run) | 65 | 52 | Avalara AvaTax +13 |
| Payments & pricing | 10% (12.5 this run) | 30 | 13 | Avalara AvaTax +17 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 79 | 78 | Avalara AvaTax +1 |
| Transparency & trust | 7% (8.8 this run) | 79 | 60 | Avalara AvaTax +19 |
| Negative events | ≤15 | 0 | -3 | |
| **Total** | | **68.8 · B** | **60.7 · C** | |

## Facts side by side

| Fact | Avalara AvaTax | Kintsugi |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Avalara, Inc. | Kintsugi AI, Inc. |
| Hosted endpoint | `https://rest.avatax.com/api/v2` | `https://api.trykintsugi.com` |
| Transports | HTTP, Streamable HTTP | HTTP, Streamable HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Paid | Paid |
| x402 | no | no |
| Licence | Proprietary service under the Avalara Service Terms. The SDKs on GitHub are Apache-2.0. The MCP repository holds a README only, with no licence file | Proprietary service under the Kintsugi Terms of Service. The Python SDK repository is MIT |
| Tools exposed | 10 | 55 |
| Read-only variant documented | no | yes |
| llms.txt | yes | yes |
| MCP registry | `com.avalara/avatax` | not listed |
| Last release | 2026-09-16 | 2026-10-07 |
| Terms last updated | 2023-05-01 | 2026-09-29 |
| Privacy policy last updated | 2022-08-08 | 2025-04-13 |
| Customer content may train models | not found in the text | yes |
| Terms restrict automated access | not found in the text | yes |
| Terms restrict benchmarking | yes | yes |
| Terms or service can change without notice | not found in the text | not found in the text |
| Arbitration or class-action waiver | not found in the text | yes |
| Popularity | 5 stars, 331k npm/wk, 38k PyPI/wk | 71 npm/wk, 10 PyPI/wk |

## Verdicts

**Avalara AvaTax.** The REST API has a public Swagger file with 491 operations, a Markdown page per endpoint and a 90-day trial with no card. Production rate limits and prices per transaction are not published, the API patch notes stop at April 2023, and the tax calculation service was degraded for about 23 hours on 5 and 6 October 2026.

**Kintsugi.** The docs are built for machine readers, with llms.txt, Markdown pages, a public OpenAPI 3.1 file, a dated changelog and an MCP server whose 55 tools carry read-only and destructive annotations. API keys need the custom-priced Premium plan and carry no scopes, no general rate limit is published, and breaking changes reached the pinned 2026-07-21 release in October 2026.

## Before you call either

### Avalara AvaTax

1. Omit `type` or send SalesOrder for an estimate. A type ending in Invoice is recorded, and `commit` set to true locks it for reporting
2. Retry a timed-out invoice with CreateOrAdjustTransaction, not CreateTransaction, which errors when a committed transaction has the same code
3. Use sandbox-rest.avatax.com with sandbox credentials for tests. Production is rest.avatax.com and the two accounts are separate
4. Add `$include=SummaryOnly` or LinesOnly to shrink transaction responses, and page lists with `$top` (1,000 at most) and `$skip`
5. Call /api/v2/utilities/ping first. It answers without credentials and shows whether the credentials sent were accepted

### Kintsugi

1. Send `Api-Key` and pin `Api-Version` (for example `2026-10-06`) on Tenanted API calls to `https://api.trykintsugi.com`. Without the header a request runs against `2026-07-21`
2. Use `x-api-key` and `x-organization-id` with `/v1` paths for the SDKs and the docs MCP server. They don't cover the Tenanted API
3. Call `POST /tax-estimations` for a quote. Nothing is stored. Record the sale with a transaction create, which answers 202, then check `processingStatus` before reading tax totals
4. Always send `externalId` on creates. A repeat with the same `externalId` and `source` returns the stored record with 200 and doesn't apply the new fields
5. Branch on the error `code`, not the message. Retry 429, 500 and 503 with exponential backoff, and restart paging from the first page on `stale_cursor`

## Questions

### Which is better for AI agents, Avalara AvaTax or Kintsugi?

Avalara AvaTax scores 68.8 (B) on agent readiness against Kintsugi's 60.7 (C), and leads in 5 of 7 scored categories. Kintsugi leads on reliability.

### Do Avalara AvaTax and Kintsugi need an API key?

Both take an API key or an OAuth sign-in.

### Can an agent call Avalara AvaTax and Kintsugi without installing anything?

Yes. Avalara AvaTax has a hosted endpoint at https://rest.avatax.com/api/v2 and Kintsugi at https://api.trykintsugi.com.


## For agents

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

## Other comparisons with Avalara AvaTax or Kintsugi

- [Anrok vs Avalara AvaTax](https://www.anchorterminal.com/compare/anrok-vs-avalara.md)
- [Anrok vs Kintsugi](https://www.anchorterminal.com/compare/anrok-vs-kintsugi.md)
- [Avalara AvaTax vs Fonoa](https://www.anchorterminal.com/compare/avalara-vs-fonoa.md)
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- [Avalara AvaTax vs Quaderno](https://www.anchorterminal.com/compare/avalara-vs-quaderno.md)
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- [Avalara AvaTax vs Vertex O Series](https://www.anchorterminal.com/compare/avalara-vs-vertex-tax.md)
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- [Fonoa vs Kintsugi](https://www.anchorterminal.com/compare/fonoa-vs-kintsugi.md)
- [Kintsugi vs Numeral](https://www.anchorterminal.com/compare/kintsugi-vs-numeral.md)
- [Kintsugi vs Quaderno](https://www.anchorterminal.com/compare/kintsugi-vs-quaderno.md)
- [Kintsugi vs TaxCloud](https://www.anchorterminal.com/compare/kintsugi-vs-taxcloud.md)
- [Kintsugi vs TaxJar](https://www.anchorterminal.com/compare/kintsugi-vs-taxjar.md)
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- [Kintsugi vs Zamp](https://www.anchorterminal.com/compare/kintsugi-vs-zamp.md)