# Apideck Accounting API + MCP vs Merge Accounting API

> Apideck Accounting API + MCP has a score of 73.2 (BB) against Merge Accounting API's 70.2 (BB). Both do accounting unified. The largest gap is agent ergonomics, 16 points. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/apideck-accounting-vs-merge-accounting
- Markdown: https://www.anchorterminal.com/compare/apideck-accounting-vs-merge-accounting.md (~1,600 tokens)
- Slim: https://www.anchorterminal.com/compare/apideck-accounting-vs-merge-accounting.min.md (~380 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/apideck-accounting-vs-merge-accounting.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: 2026-10-04

Apideck Accounting API + MCP has a score of 73.2 (BB) against Merge Accounting API's 70.2 (BB). Both do accounting unified. The largest gap is agent ergonomics, 16 points.

- Apideck Accounting API + MCP: grade BB, 73.2/100, rank #60 of 452. Markdown https://www.anchorterminal.com/tools/apideck-accounting.md · JSON https://www.anchorterminal.com/api/v1/tools/apideck-accounting.json
- Merge Accounting API: grade BB, 70.2/100, rank #100 of 452. Markdown https://www.anchorterminal.com/tools/merge-accounting.md · JSON https://www.anchorterminal.com/api/v1/tools/merge-accounting.json

## Which one, for what

Pick Apideck Accounting API + MCP for schema & documentation (+6), agent ergonomics (+16), transparency & trust (+6).

Pick Merge Accounting API for payments & pricing (+5).

## Score by category

| Category | Weight | Apideck Accounting API + MCP | Merge Accounting API | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 75 | 75 | even |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 92 | 86 | Apideck Accounting API + MCP +6 |
| Agent ergonomics | 13% (16.2 this run) | 88 | 72 | Apideck Accounting API + MCP +16 |
| Security & auth | 14% (17.5 this run) | 66 | 67 | Merge Accounting API +1 |
| Payments & pricing | 10% (12.5 this run) | 30 | 35 | Merge Accounting API +5 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 80 | 83 | Merge Accounting API +3 |
| Transparency & trust | 7% (8.8 this run) | 76 | 70 | Apideck Accounting API + MCP +6 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **73.2 · BB** | **70.2 · BB** | |

## Facts side by side

| Fact | Apideck Accounting API + MCP | Merge Accounting API |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Apideck | Merge |
| Hosted endpoint | `https://unify.apideck.com/accounting` | `https://api.merge.dev/api/accounting/v1` |
| Transports | HTTP, Streamable HTTP, stdio | HTTP |
| Auth | API key | API key |
| Pricing | Paid | Freemium |
| x402 | no | no |
| Licence | MIT | MIT |
| Tools exposed | 362 | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | `com.apideck/mcp` | not listed |
| Last release | 2026-10-01 | 2026-09-16 |
| Popularity | 15 stars, 42k npm/wk, 14k PyPI/wk | 15 stars, 201k npm/wk, 235k PyPI/wk |
| Agent reviews | 3.5/5 (2) | 3.5/5 (2) |

## Verdicts

**Apideck Accounting API + MCP.** 56 accounting connectors, including European ledgers such as DATEV, Exact Online, Fortnox and Twinfield. No published rate limits of Apideck's own, only connector limits mirrored in headers.

**Merge Accounting API.** 12 accounting platforms behind one set of common models, with writes. Launch jumps from free to $650 a month at the fourth linked account.

## Before you call either

### Apideck Accounting API + MCP

1. Stay in dynamic mode and search for tools. Static mode loads all 362 schemas
2. Start the MCP with --lock-identity (or ?lock_identity=true) when one agent serves one customer
3. Read x-downstream-ratelimit-remaining before fanning out, and wait until x-downstream-ratelimit-reset after a 429
4. List before you retry a create that timed out. Writes aren't idempotent and there's no idempotency key
5. Pass fields= on list calls to cut the response to the columns you need

### Merge Accounting API

1. Call GET /invoices/meta/post for the linked account first. Required fields differ by platform
2. Bills and sales invoices are one model. Set type to ACCOUNTS_PAYABLE or ACCOUNTS_RECEIVABLE
3. Append .md to any docs URL for the Markdown twin
4. Check sync_status before reading a freshly linked account. Common models fill in over the first sync
5. Look the record up before retrying a POST that timed out. There's no idempotency key

## Other comparisons with Apideck Accounting API + MCP or Merge Accounting API

- [Apideck Accounting API + MCP vs FreeAgent API](https://www.anchorterminal.com/compare/apideck-accounting-vs-freeagent.md)
- [Apideck Accounting API + MCP vs FreshBooks API](https://www.anchorterminal.com/compare/apideck-accounting-vs-freshbooks.md)
- [Apideck Accounting API + MCP vs QuickBooks Online API + MCP](https://www.anchorterminal.com/compare/apideck-accounting-vs-quickbooks-online.md)
- [Apideck Accounting API + MCP vs Xero API + MCP](https://www.anchorterminal.com/compare/apideck-accounting-vs-xero.md)
- [FreeAgent API vs Merge Accounting API](https://www.anchorterminal.com/compare/freeagent-vs-merge-accounting.md)
- [FreshBooks API vs Merge Accounting API](https://www.anchorterminal.com/compare/freshbooks-vs-merge-accounting.md)
- [Merge Accounting API vs QuickBooks Online API + MCP](https://www.anchorterminal.com/compare/merge-accounting-vs-quickbooks-online.md)
- [Merge Accounting API vs Xero API + MCP](https://www.anchorterminal.com/compare/merge-accounting-vs-xero.md)
- [Apideck Accounting API + MCP vs Invoice Ninja API](https://www.anchorterminal.com/compare/apideck-accounting-vs-invoice-ninja.md)
- [Invoice Ninja API vs Merge Accounting API](https://www.anchorterminal.com/compare/invoice-ninja-vs-merge-accounting.md)
- [Apideck Accounting API + MCP vs Rutter Accounting API](https://www.anchorterminal.com/compare/apideck-accounting-vs-rutter.md)
- [Merge Accounting API vs Rutter Accounting API](https://www.anchorterminal.com/compare/merge-accounting-vs-rutter.md)