# Invoice Ninja API vs Puzzle API and MCP (slim)

> Invoice Ninja scores 49.1 (D) to Puzzle's 46.2 (D) for invoicing. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/invoice-ninja-vs-puzzle.md (~3,950 tokens) · this version ~2,180 tokens · JSON https://www.anchorterminal.com/compare/invoice-ninja-vs-puzzle.json · canonical https://www.anchorterminal.com/compare/invoice-ninja-vs-puzzle
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-07
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

Invoice Ninja API scores 49.1 (D) on agent readiness against Puzzle API and MCP's 46.2 (D), and leads in 6 of 7 scored categories. Puzzle API and MCP leads on security & auth. Both do invoicing.

- Invoice Ninja API: D 49.1, rank #1106 of 1510 · https://www.anchorterminal.com/tools/invoice-ninja.min.md
- Puzzle API and MCP: D 46.2, rank #1180 of 1510 · https://www.anchorterminal.com/tools/puzzle.min.md
- Invoice Ninja API, good for An agent that quotes, invoices, chases and records payments for a small business, or for anyone who wants the billing system on their own server. Ahead on Reliability, 41 against 15; Payments & pricing, 35 against 15; Maintenance & community, 83 against 53; Transparency & trust, 63 against 49.
- Puzzle API and MCP, good for Startups already on Puzzle who want an assistant to answer finance questions and draft bookkeeping. xero, quickbooks-online and pennylane are the nearest listings; teams wanting a self-serve API should look there. Ahead on Security & auth, 73 against 53. Also No incidents deducted, where Invoice Ninja API loses 6 points for them.

| Category | Invoice Ninja API | Puzzle API and MCP |
| --- | --- | --- |
| Reliability (16%) | 41 | 15 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 66 | 65 |
| Agent ergonomics (13%) | 60 | 56 |
| Security & auth (14%) | 53 | 73 |
| Payments & pricing (10%) | 35 | 15 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 83 | 53 |
| Transparency & trust (7%) | 63 | 49 |

| Fact (where they differ) | Invoice Ninja API | Puzzle API and MCP |
| --- | --- | --- |
| Kind | HTTP API | MCP server |
| Vendor | Invoice Ninja | Puzzle Financial Inc. |
| Hosted endpoint | `https://invoicing.co/api/v1` | `https://app.puzzle.io/mcp` |
| Transports | HTTP | Streamable HTTP |
| Auth | API key | OAuth |
| Pricing | Freemium | Paid |
| Licence | Elastic License 2.0 | none |
| Read-only variant documented | no | yes |
| llms.txt | no | yes |
| MCP registry | not listed | `io.puzzle/puzzle` |
| Last release | 2026-10-18 | 2026-10-05 |
| Terms last updated | not read yet | 2023-06-01 |
| Privacy policy last updated | not read yet | 2025-12-19 |
| Customer content may train models | not read yet | not found in the text |
| Terms restrict automated access | not read yet | yes |
| Terms restrict benchmarking | not read yet | not found in the text |
| Terms or service can change without notice | not read yet | not found in the text |
| Arbitration or class-action waiver | not read yet | yes |
| Popularity | 10k stars | none |
| Agent reviews | 2.5/5 (2) | none |

Why the edge:
- Maintenance & community, Invoice Ninja API +30: Invoice Ninja API 83 (v5.13.49 on 18 October 2026 (30). 20 tagged releases on v5-stable since 6 August, from v5.13.30 to v5.13.49 (20). Pull requests merge within days on v5-stable. We couldn't see issue reply times from git (15). Official PHP SDK, v2.0.0 tagged on 2 November 2026 after v1.4.0 in January 2025. No MCP server (8). PHPUnit CI runs the test suite across PHP 8.2 to 8.5 on every push to v5-stable and v5-develop, plus Dependabot (10). 30 + 20 + 15 + 8 + 10 = 83.); Puzzle API and MCP 53 (The MCP registry entry was published on 5 October 2026, 32 days before this check, and Puzzle's MCP post is dated 26 October (20). No release log, so changes in the 90 days can't be counted beyond the registry entry and the MCP launch (5). A help centre and support contact, but no public changelog or issue tracker (8). io.puzzle/puzzle sits under a domain-verified namespace in the official registry (15). No SDK or package to judge (5). 20 + 5 + 8 + 15 + 5 = 53.)
- Reliability, Invoice Ninja API +26: Invoice Ninja API 41 (Oh Dear status page watching invoiceninja.com and invoicing.co, with no component for the API itself; it now links an incident history page (15). The history page lists one event, invoiceninja.com down for one minute on 29 October 2026, and doesn't say how far back it reaches, so the 90-day record isn't established and the line keeps 5. The docs give no numbers. The source sets 1,000 requests a minute per IP and per token on the hosted service, 20 a minute on report exports and no limit when self-hosted, counted at half as on 1 October (8). 429 appears only as a row in the error table, with no backoff or retry guidance (3, the 1 October partial). No SLA, and the terms say Invoice Ninja "strives to ensure maximum uptime" (0). GA (10). 15 + 5 + 8 + 3 + 0 + 10 = 41.); Puzzle API and MCP 15 (Hosted reading. status.puzzle.io exists but answered 403 to our reader, so no status page or history could be read (0, then 5 for no readable history). No rate limits found in the API docs (0). The errors page documents 409 RESOURCE_PROCESSING with retry later and 500 with retry, but no 429 or idempotency guidance (5). No SLA (0). MCP read access is live, write access is a beta, and the API docs say the API is under development (5). 0 + 5 + 0 + 5 + 0 + 5 = 15.)
- Security & auth, Puzzle API and MCP +20: Invoice Ninja API 53 (API tokens per user, created and revoked under Settings, Account Management, Integrations, in a header and never a URL. No per-token scopes (20). No read-only token. Invoices stay drafts unless the call asks otherwise (5). Returns client and product text that other people wrote, and stored XSS advisories came through invoice line items, product notes and the terms field, with no injection guidance for API consumers (3). Activity log and an activities report export (10). SECURITY.md with a disclosure email, advisories published on GitHub, and a SOC 2 page (Security, Availability, Confidentiality and Processing Integrity, report under NDA on request) with a PCI-DSS claim. The page names neither the SOC 2 type nor the auditor. No security.txt or bug bounty (15, as brex). 20 + 5 + 3 + 10 + 15 = 53.); Puzzle API and MCP 73 (OAuth for MCP with a per-company choice and read-only default, and OAuth 2.0 with granular scopes on the API, defaulting to read-only scopes (28). Read-only by default, writes an opt-in beta with confirmation for each change (18). Bank descriptions and vendor names are third-party text, and no prompt-injection guidance was found (3). Every API request is logged per the docs, and a firm activity endpoint returns an audit log (12). A SOC 2 claim in the API docs and a bug bounty policy page; no security.txt (12). 28 + 18 + 3 + 12 + 12 = 73.)
- Payments & pricing, Invoice Ninja API +20: Invoice Ninja API 35 (No x402, MPP or L402 (0). Hosted plan prices are public, Pro $14 a month, Enterprise $18 to $300, Premium Business from $280 a year (10). Hosted Free (5 clients, no card) has no REST API, but self-hosting is free with every feature, which we counted at three quarters (15). The public demo at demo.invoiceninja.com takes the token TOKEN with no signup, though it's a shared demo, not your own company (10). 0 + 10 + 15 + 10 = 35.); Puzzle API and MCP 15 (No x402, MPP or L402 (0). Plan prices are public, but there is no per-call price and the API has no published price (10). "Try for free" on every plan, with trial length and card requirement not stated on the pages read (5). A person signs up and authorises in a browser, and API credentials come by email (0). 0 + 10 + 5 + 0 = 15.)
- Transparency & trust, Invoice Ninja API +14: Invoice Ninja API 63 (Source-available under the Elastic License 2.0, which is clear but isn't an OSI licence, so we scored between closed and open (20). The privacy policy on invoiceninja.com names eight vendors (OVH Cloud added) and a DPA, and now states one retention period (free accounts inactive for three months are deleted), and the terms (version 1.0.2, effective 1 February 2026) name Florida law. No full retention schedule or registered address, so 15 plus 3 (18). No deprecation policy found, only release notes (3). Self-hosted error reporting is opt-in by checkbox and disclosed. Vendors named without data locations (16). 20 + 18 + 3 + 16 = 57.); Puzzle API and MCP 49 (Closed service with published terms naming Puzzle Financial Inc. (15). A privacy policy effective 19 December 2025; the security page says data stays on US servers and isn't shared or sold (15). The API docs promise documented endpoints stay stable but give no deprecation policy (5). Sub-processors not found, though the server location is stated (8). 15 + 15 + 5 + 8 = 43.)