MCP Comparison · 2026
Clay vs Harmonic MCP Server
Comparing Clay and Harmonic as MCP servers? Clay (chatgpt app) is best when conversational access to clay inside chatgpt. Harmonic (chatgpt app) is best when conversational access to harmonic inside chatgpt. Both run as Model Context Protocol servers and can coexist in the same client. Updated 2026.
Side-by-side specs
Pulled from each MCP's verified fact sheet.
| Clay | Harmonic | |
|---|---|---|
| Primary function | ChatGPT App | ChatGPT App |
| Maintainer | Clay | Harmonic |
| Pricing | Free | Free |
| Setup complexity | Low · ~< 1 min | Low · ~< 1 min |
| Transport | Streamable HTTP | Streamable HTTP |
| Auth model | OAuth 2.1 | OAuth 2.1 |
| License | Proprietary | Proprietary |
| Language | — | — |
| Latest version | — | — |
| Compatible clients | ChatGPT | ChatGPT |
| Last verified | 2026-04-30 | 2026-04-30 |
Which one should you pick?
Decision rubric drawn from each MCP's documented strengths.
Choose Clay
- Conversational access to Clay inside ChatGPT
- In-chat workflows that benefit from rich UI widgets
- One-click OAuth on Free / Go / Plus / Pro plans
Choose Harmonic
- Conversational access to Harmonic inside ChatGPT
- In-chat workflows that benefit from rich UI widgets
- One-click OAuth on Free / Go / Plus / Pro plans
Pick something else if…
- Use outside ChatGPT
Feature breakdown
Key capabilities each server ships out of the box.
Clay
- Listed in the official ChatGPT Apps directory
- One-click OAuth — no JSON config, no install command
- Available to logged-in ChatGPT users on supported plans
- Built on the OpenAI Apps SDK (MCP under the hood)
- Reviewed and approved by OpenAI before publication
Harmonic
- Listed in the official ChatGPT Apps directory
- One-click OAuth — no JSON config, no install command
- Available to logged-in ChatGPT users on supported plans
- Built on the OpenAI Apps SDK (MCP under the hood)
- Reviewed and approved by OpenAI before publication
Install snippets
Open the detail page for ready-to-paste config for every major client.
FAQ
Clay vs Harmonic: which MCP server should I use?
Pick Clay when conversational access to clay inside chatgpt. Pick Harmonic when conversational access to harmonic inside chatgpt. Clay is built for chatgpt app, while Harmonic focuses on chatgpt app.
Can I run both Clay and Harmonic together?
Yes. MCP clients run each server as a separate process and surface every server's tools simultaneously, so you can install both and let your agent decide which to call. Be deliberate with auth scopes when stacking servers.
How fresh is this comparison?
Updated for 2026. Clay's last verification: 2026-04-30. Harmonic's last verification: 2026-04-30. We refresh detail-page facts on every catalog rebuild.
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