M91 vs Stacktrace
A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.
M91 compared with Stacktrace
| Detail | 
M91 | 
Stacktrace |
|---|
| What it does | Human-in-the-loop approval for AI agents
| Real-time steering and guardrails for AI agents
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| Stage | Not given
| Not given
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| Founded | Not given
| Not given
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| Based in | Not given
| Not given
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| Pricing model | Free
| Freemium
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| Pricing | Free forever with all features included
| Team: Free per organization, unlimited users, 200 session-hours per month. Enterprise and Gateway: Custom pricing, billed annually.
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| Key features | - Alerts on iPhone and Android with answer buttons
- Phone call escalation for high and critical alerts
- Breaks through silent mode and Do Not Disturb
- Attachments and notes on every alert
- Broadcast to a channel with one person taking ownership
- See who acted and who ignored alerts
- Answer buttons set by you or your AI
- Callback webhooks to return answers to your code
- Setup via pasted prompt or API key-free send link
- Integration with AI frameworks, automation platforms and HTTP API
| - Reads every tool call agents make and blocks unsafe ones before they run
- Catches stalled and runaway sessions while they run
- Steers agents back when they go past what was asked
- Tracks every session's tokens against usual usage
- Stops credential and data leaks before they leave the machine
- Inventories all agents, MCP servers and skills in use
- Blocks dangerous calls before they run in agent hooks and at the gateway
- Sends every finding to Slack, webhook or SIEM
- Verifies each agent's identity before access
- Keeps audit-grade masked records of every action and decision
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| What makes it different | - Full-volume alerts that interrupt even when phone is silenced
- No SDK, API key or card required to start
- Free forever with every feature for every team member
- Escalates to phone calls for critical alerts that go unanswered
- Works with existing AI agents, workflows and monitoring tools
| - Works with Claude Code, Codex, Cursor, Devin and more
- Runs on your machines, gateways and in the cloud
- Active steering corrects or stops drifting runs
- One policy applied across all MCP servers, plugins and skills
- Continuously monitors components for known vulnerabilities
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| Community votes | 0 | 0 |
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| DR (Domain Rating by Ahrefs) | 73 ● no change since last check | 3 ▲ +2 (up) since last check |
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| Trust Flow (Majestic) | 1 | 13 |
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| Citation Flow (Majestic) | 1 | 25 |
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| Referring domains (Majestic) | 0 | 23 |
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5 details filled in for both companies.
More alternatives to M91 More alternatives to Stacktrace