Head to head · Payroll run · October 2026 research run
Gusto vs Zeal
Gusto scores 63.3 (B) on agent readiness against Zeal's 45.4 (E), and leads in every scored category. Both do payroll run.
Which one, for what
Gusto B
Good for A software platform that wants to run US payroll for its own customers and can pass Gusto's partner reviews.
Ahead on
- Reliability, 58 against 42
- Schema & documentation, 86 against 68
- Agent ergonomics, 82 against 63
- Security & auth, 60 against 34
- Payments & pricing, 15 against 0
- Maintenance & community, 76 against 61
- Transparency & trust, 61 against 51
Watch for
Production keys need commercial, security and implementation reviews with Gusto's partnerships team, and the docs say not all use cases are supported
Zeal E
Good for A US staffing platform, marketplace or workforce product that will sign a partnership and run payroll for many employers under its own brand, including daily and on-demand pay.
Also in its favour
- A hosted endpoint, with nothing to install
Watch for
No self-serve signup. Zeal's team creates the partner account after a demo request, and no price is published
Score by category
| Category | Weight this run | Gusto | Zeal | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 58 | 42 | Gusto +16 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 86 | 68 | Gusto +18 |
| Agent ergonomics | 13%16.2 | 82 | 63 | Gusto +19 |
| Security & auth | 14%17.5 | 60 | 34 | Gusto +26 |
| Payments & pricing | 10%12.5 | 15 | 0 | Gusto +15 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 76 | 61 | Gusto +15 |
| Transparency & trust | 7%8.8 | 61 | 51 | Gusto +10 |
| Negative events | ≤15 | 0 | 0 | |
| Total | 63.3 · B | 45.4 · E |
Facts side by side
| Fact | Gusto | Zeal |
|---|---|---|
| Kind | HTTP API | HTTP API |
| Vendor | Gusto, Inc. | Puzzl Group Inc. |
| Hosted endpoint | no (local only) | https://api.zeal.com |
| Transports | HTTP | HTTP |
| Auth | OAuth | API key |
| Pricing | Paid | Paid |
| x402 | no | no |
| Licence | Proprietary service under Gusto's API Policy and Developer Terms of Service. The API clients on GitHub are MIT, and the React SDK and the Gusto CLI are Apache-2.0 | Proprietary service. The npm SDK declares MIT. The SDK repositories on GitHub carry no licence file |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-10-01 | 2026-07-31 |
| Terms last updated | couldn't be read | 2026-01-16 |
| Privacy policy last updated | no document linked | 2026-01-16 |
| Customer content may train models | couldn't be read | not found in the text |
| Terms restrict automated access | couldn't be read | yes |
| Terms restrict benchmarking | couldn't be read | not found in the text |
| Terms or service can change without notice | couldn't be read | yes |
| Arbitration or class-action waiver | couldn't be read | not found in the text |
| Popularity | 2 stars, 25k npm/wk | 0 stars, 8 npm/wk |
Verdicts
Gusto
This listing covers the Embedded Payroll API. Every reference page carries an OpenAPI 3.1 definition, payroll is calculated as a preview before submission, and each API version gets 12 months of deprecation support. Production needs commercial and security approval, no price was readable, and the status page lists 11 incidents between 14 July and 5 October 2026, five marked major.
Zeal
Graded on the partner REST API at api.zeal.com, which is the only access route. Three OpenAPI specs, llms.txt, a test environment that moves no money, a preview endpoint and a per-cheque approval flag are documented. Access starts with a demo request, prices are not published, each environment has one unscoped key, and no status page or working changelog was found.
Before you call either
Gusto
- Develop against https://api.gusto-demo.com. Production at https://api.gusto.com needs keys Gusto issues after its reviews
- Send
X-Gusto-API-Version: 2026-06-15on every call. Without it the application's minimum version applies - Send the resource's current
versionwith every PUT, and only the fields to change. A stale version returns 409 - Calculate and submit return 202. Poll GET on the payroll until
calculated_atis set or the status is processed, and readsubmission_blockersfirst - For a company already on Gusto, the Embedded API is the wrong route. Use the Gusto CLI or the MCP server at https://mcp.api.gusto.com, which draft payroll but can't submit it
Zeal
- Use the Test API key until a person has approved live payroll. Error code 0 (403) means the account has no production access
- Send
companyIDon almost every call andpartnerIDon partner-level calls, in the body for POST and PATCH and the query for GET - Create cheques with
approval_required: true, run POST /preview/checks, then PATCH /employeeCheck withapproved: true. Without the flag Zeal processes pending cheques automatically - Send
x-idempotency-keyon every create so a retry within 24 hours doesn't pay twice - Previews and reports are jobs. Keep the
job_idand poll GET /preview or GET /reports, or wait for the Job Queue webhook - Check dates must be bank days and submitted before 2 PM Pacific two bank days ahead, or the call fails with code 89
Questions
Which is better for AI agents, Gusto or Zeal?
Gusto scores 63.3 (B) on agent readiness against Zeal's 45.4 (E), and leads in every scored category.
Do Gusto and Zeal need an API key?
Gusto uses an OAuth sign-in. Zeal needs an API key.
Can an agent call Gusto and Zeal without installing anything?
No hosted endpoint is listed for Gusto. Zeal has a hosted endpoint at https://api.zeal.com.
Other comparisons with Gusto or Zeal
Machine-readable
- This page as Markdown
/compare/gusto-vs-zeal.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/gusto.json·/api/v1/tools/zeal.json - From a terminal
anchor compare gusto zeal(the CLI) - Over MCP
compare_tools {"a": "gusto", "b": "zeal"}at/mcp, no key