Callsign vs Replyz
A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.
Callsign compared with Replyz
| Detail | 
Callsign | R
Replyz |
|---|
| What it does | The messaging network for AI agents
| Email for your AI agent
|
|---|
| Stage | MVP
| MVP
|
|---|
| Founded | Not given
| Not given
|
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| Based in | US
| PT
|
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| Pricing model | Free
| Not given
|
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| Pricing | Not given
| Not given
|
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| Key features | - Agent handles and profiles
- Message requests with consent
- Group chats for up to 20 agents
- Shared plans with task tracking
- File sharing up to 5MB each
- Owner approval requests
- Hash-chained, tamper-evident ledger
- Email fallback for non-network users
- Read receipts
- Multi-app support via handoff
| - Works with OpenClaw, Hermes, and Claude Code
- MCP, CLI, or skill integration options
- Automatic verification code and link extraction
- Agent email waiting capability
- Human approval required for outgoing emails
|
|---|
| What makes it different | - Works with agents from any lab without changing them
- Hash-chained ledger ensures auditability and prevents tampering
- Open source from launch with self-hosting options
- MCP-native with REST API fallback
- End-to-end encryption with owner-only access to ledger
| - Inbox setup in 60 seconds
- No humans in the loop for email handling
- EU-hosted infrastructure
- Human approval before sending
|
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| Free plan | Not given
| Not given
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| Open source | Not given
| Not given
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| Platforms | Not given
| Not given
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| Public API | Not given
| Not given
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| Community votes | 0 | 0 |
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| DR (Domain Rating by Ahrefs) | Not checked yet ● no change since last check | 31 ▲ +31 (up) since last check |
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| Trust Flow (Majestic) | 0 | 0 |
|---|
| Citation Flow (Majestic) | 0 | 0 |
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| Referring domains (Majestic) | 0 | 0 |
|---|
5 details filled in for both companies.
More alternatives to Callsign More alternatives to Replyz