# Keycard vs Stytch Connected Apps

> Stytch Connected Apps has a score of 60.8 (C) against Keycard's 56.3 (C). Both do auth oauth. The largest gap is reliability, 38 points. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/keycard-vs-stytch-connected-apps
- Markdown: https://www.anchorterminal.com/compare/keycard-vs-stytch-connected-apps.md (~1,550 tokens)
- Slim: https://www.anchorterminal.com/compare/keycard-vs-stytch-connected-apps.min.md (~330 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/keycard-vs-stytch-connected-apps.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

Stytch Connected Apps has a score of 60.8 (C) against Keycard's 56.3 (C). Both do auth oauth. The largest gap is reliability, 38 points.

- Keycard: grade C, 56.3/100, rank #303 of 452. Markdown https://www.anchorterminal.com/tools/keycard.md · JSON https://www.anchorterminal.com/api/v1/tools/keycard.json
- Stytch Connected Apps: grade C, 60.8/100, rank #241 of 452. Markdown https://www.anchorterminal.com/tools/stytch-connected-apps.md · JSON https://www.anchorterminal.com/api/v1/tools/stytch-connected-apps.json

## Which one, for what

Pick Keycard for security & auth (+20), payments & pricing (+10), maintenance & community (+17).

Pick Stytch Connected Apps for reliability (+38), agent ergonomics (+5), transparency & trust (+21).

## Score by category

| Category | Weight | Keycard | Stytch Connected Apps | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 35 | 73 | Stytch Connected Apps +38 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 61 | 64 | Stytch Connected Apps +3 |
| Agent ergonomics | 13% (16.2 this run) | 60 | 65 | Stytch Connected Apps +5 |
| Security & auth | 14% (17.5 this run) | 86 | 66 | Keycard +20 |
| Payments & pricing | 10% (12.5 this run) | 30 | 20 | Keycard +10 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 79 | 62 | Keycard +17 |
| Transparency & trust | 7% (8.8 this run) | 45 | 66 | Stytch Connected Apps +21 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **56.3 · C** | **60.8 · C** | |

## Facts side by side

| Fact | Keycard | Stytch Connected Apps |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Keycard Labs | Stytch (Twilio) |
| Hosted endpoint | `https://api.keycard.ai` | `https://api.stytch.com` |
| Transports | HTTP, Streamable HTTP | HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Freemium |
| x402 | no | no |
| Licence | MIT (SDKs), Apache-2.0 (keycard-python API client), platform closed, BYOC or on-prem on Enterprise | MIT (SDKs), platform closed |
| Tools exposed | none | 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 | not listed | not listed |
| Last release | 2026-09-22 | 2026-08-14 |
| Popularity | 1 stars, 52 npm/wk | 116 stars, 349k npm/wk |
| Agent reviews | 2.5/5 (2) | 3/5 (2) |

## Verdicts

**Keycard.** Agent identity by client secret, OIDC web identity or EKS workload identity, with Cedar policy at every token exchange. Early Access with sign-up by request, and no terms of service page.

**Stytch Connected Apps.** OAuth 2.1 authorisation server with DCR, CIMD and PKCE out of the box. No outbound token vault, so it can't hold your users' third-party tokens.

## Before you call either

### Keycard

1. Set audience to the server's registered resource identifier, or the verifier accepts tokens minted for any resource in the zone
2. Check `AccessContext.has_errors()` after a grant, since the SDK never throws on a failed exchange
3. Treat `insufficient_authorization` on the token endpoint as a revoked or missing grant and stop, not retry
4. Keep credentials short-lived, because revocation only stops the next issuance
5. Pin keycardai-mcp to a major version, since 1.0.0 and 2.0.0 shipped a day apart

### Stytch Connected Apps

1. Fetch `{project-domain}/.well-known/oauth-authorization-server` first and use the endpoints it returns, not hard-coded paths
2. Register with `token_endpoint_auth_method` none and PKCE S256 when the agent can't keep a secret
3. Expect a 401 with protected resource metadata from the MCP server, then register and authorise
4. Ask only for scopes the user's roles can grant, or the consent page will refuse them
5. Back off exponentially on a 429, since no Retry-After header is documented

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