AgentFirstStack

AgentFirstStack provides free, open-source analytics, tag management, email inboxes, and session replay set up by coding agents.

AgentFirstStack offers free, open-source analytics, tag management, email inboxes, and session replay designed for AI coding agents. A coding agent uses a plain-text manual and an API or MCP server to create accounts, configure sites, and verify tracking without a signup form or dashboard. The analytics service tracks cookieless visitors, custom events, goals, funnels, and revenue. The tag manager handles server-side and browser event delivery to ad platforms with deduplication. The mail service provides instant inboxes for receiving verification codes and handling emails. The session replay tool captures interactions with text masking and frustration detection. Users retain control of ad credentials and claim projects via a dashboard link.

AgentFirstStack at a glance

Best for: Software engineer, Product manager
Runs on: Web, API, self-hosted, open source
Pricing: Free plan; self-hosted open source under AGPL-3.0
Released: November 2026
Category: AI productivity tool
Website: agentfirststack.com

Key features

Cookieless visitor analytics
Server-side tag management
Instant agent email inboxes
Session replay with text masking
MCP server and REST API
Plain-text manual for coding agents
Automated setup and verification

Use it for

Setting up analytics and conversion tracking via a coding agent
Managing tags and event dispatching for ad platforms
Providing automated email inboxes for user signups and tests
Analyzing user sessions and frustration metrics

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AgentsView — It keeps your AI coding session archive local by default while tracking costs and activity.
zerostack — Minimal memory footprint and high CPU efficiency compared to JS-based agents.
Agentfork — It replays steps from cache and runs sweeps to provide pass rates instead of anecdotes.

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