# Kintsugi (slim)

> Kintsugi is a hosted sales tax, VAT and GST compliance platform. Its API estimates tax, records transactions, customers and exemptions, and manages nexus, registrations and filings. Two MCP servers connect AI assistants to the API and to account data.

- Full: https://www.anchorterminal.com/tools/kintsugi.md (~8,100 tokens) · this version ~1,830 tokens · JSON https://www.anchorterminal.com/tools/kintsugi.json · canonical https://www.anchorterminal.com/tools/kintsugi
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-08

**C · 60.7/100 · rank #392 of 722 · #3 in Tax calculation & compliance · not agent-ready · confidence medium**


Assessment: 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.

## Facts

- Kind: HTTP API · vendor: Kintsugi AI, Inc. · category: Tax calculation & compliance · legal entity: Kintsugi AI, Inc. · provenance 75/100
- Endpoint: `https://api.trykintsugi.com` (HTTP, Streamable HTTP)
- Auth: OAuth or key · pricing: Paid · x402: no · licence: Proprietary service under the Kintsugi Terms of Service. The Python SDK repository is MIT
- Probe metrics: not measured yet (probes haven't run)
- APIs: Tenanted API at https://api.trykintsugi.com with no path prefix, 287 operations in each of releases 2026-07-21 and 2026-10-06. v1 under `/v1`, 55 documented operations, labelled legacy. A separate Partner API is documented too
- Calculation: `POST /tax-estimations` (v1 `POST /v1/tax/estimate`) returns tax without storing anything. Tax is zero where no active registration covers the destination unless `simulateActiveRegistration` is set
- Transactions: Creating a transaction answers 202 and tax is calculated just after. Credit notes record refunds. Creates are idempotent on `externalId` and `source`
- MCP servers: Docs and API server at https://docs.trykintsugi.com/mcp, Streamable HTTP, 55 tools over v1 with the API key in headers. Account-data server at https://mcp.trykintsugi.com/mcp, OAuth 2.1, 46 read-only tools per Kintsugi
- Credentials: Organisation API key with optional expiry (one month, six months, one year or never), several keys allowed, no scopes. OAuth 2.1 with PKCE, dynamic client registration and scope `read:user_data` for the account-data MCP server
- Rate limits: No general limit published. `POST /filings/{filing_id}/enhanced-data/rebuild` allows 10 requests a minute. 429 answers with code `rate_limited`
- Errors: Tenanted API envelope of `code`, `message`, `requestId` and `errors`, with 20 documented codes and four field-level codes. v1 error shapes vary by endpoint
- Paging: Keyset cursors with `limit` and `cursor` on the Tenanted API, plus `sort`, `order` and filters. v1 uses `page` and `size`
- Pricing: Free $0. Starter from $75 per filing or registration. Premium quoted by sales, and the only plan listed with API access, SDKs and coverage outside the US
- SDKs: Python `kintsugi-tax-platform-sdk` 0.13.0 (15 September 2026), TypeScript `@kintsugi-tax/tax-platform-sdk` 0.10.2 (7 July 2026), Java, PHP and Ruby, generated with Speakeasy, covering v1 only
- Certifications: SOC 2 Type II per trykintsugi.com/security-and-privacy. AES-256 at rest and TLS 1.2 or later in transit, per the same page
- Status: Statuspage at https://status.trykintsugi.com with five components, among them API and Filings and Registrations
- Data: Processed in the United States per the DPA of 26 August 2026. 60 days to retrieve data after termination, and deletion on request, per the terms
- Prices: Starter plan, per filing or registration $75 per transaction

- Scores: Reliability 73, Performance pending, Schema & documentation 87, Agent ergonomics 75, Security & auth 52, Payments & pricing 13, Task success pending, Maintenance & community 78, Transparency & trust 60 · negative events -3 · total over the 7 assessed categories
- Why: Reliability, Graded on the public API with the hosted lines. · Schema & documentation, OpenAPI 3.1 is public at `https://api.trykintsugi.com/openapi.json` with 901 operations, covering v1, partner and admin paths. · Agent ergonomics, List endpoints take `limit` and a cursor, with no field selection found. · Security & auth, Two credential models. · Payments & pricing, No x402, MPP or L402 (0). · Maintenance & community, The API changelog's newest entry is 7 October 2026, and release 2026-10-06 shipped the day before (30). · Transparency & trust, Closed service with clear terms, last updated 29 September 2026, naming Kintsugi AI, Inc.
- Sources: 23, open questions: 10, both in the full twin
- Capabilities: tax.calculate, tax.transactions, tax.filing, tax.exemptions
- JSON: https://www.anchorterminal.com/api/v1/tools/kintsugi.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/kintsugi.svg` or a link to https://www.anchorterminal.com/tools/kintsugi from a page on trykintsugi.com or one of its subdomains, or the README of github.com/kintsugi-tax/kintsugi-tax-python-sdk, then `POST https://www.anchorterminal.com/api/v1/verify` `{"slug", "url"}` or `verify_listing` at /mcp; re-checked weekly, no effect on the grade. Snippets in the full twin.

## Before you call it

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`

## Connect

```bash
pip install kintsugi-tax-platform-sdk
```

```bash
curl https://api.trykintsugi.com/products/categories \
  -H "Api-Key: $KINTSUGI_API_KEY" \
  -H "Api-Version: 2026-07-21"
```
Full config and headless snippets are in the full page. Through letme (picks today, calling later): https://letme.dev/kintsugi

## Similar tools

| Tool | Grade | Score | Shared capabilities | Slim |
| --- | --- | --- | --- | --- |
| Avalara AvaTax | B | 68.8 | tax.calculate, tax.transactions, tax.exemptions, tax.filing | https://www.anchorterminal.com/tools/avalara.min.md |
| Anrok | C | 61.6 | tax.calculate, tax.transactions, tax.exemptions, tax.filing | https://www.anchorterminal.com/tools/anrok.min.md |
| Zamp | D | 49.5 | tax.calculate, tax.transactions, tax.filing, tax.exemptions | https://www.anchorterminal.com/tools/zamp.min.md |
| Numeral | D | 49.3 | tax.calculate, tax.transactions, tax.exemptions, tax.filing | https://www.anchorterminal.com/tools/numeral.min.md |
| TaxJar | C | 57.6 | tax.calculate, tax.transactions, tax.exemptions | https://www.anchorterminal.com/tools/taxjar.min.md |


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