Claude for Chrome vs Project Mariner
Claude for Chrome vs Project Mariner: side-by-side comparison of two computer-use & desktop agents systems — architecture, taxonomy, license, pricing, MCP/A2A support, and direct edges.
Claude for Chrome · Project Mariner
Cost & capability
| Claude for Chrome | Project Mariner | |
|---|---|---|
| Capability band | competent | competent |
| Capability composite | 74 | 73 |
| Cost tier | premium | mid |
| Use cases | Scoped Agentic | Scoped Agentic |
Where they differ (14)
Rows where both sides have data and the values disagree — the shortlist of dimensions that actually distinguish these two systems.
| Claude for Chrome | Project Mariner | |
|---|---|---|
| Capability composite | 74 | 73 |
| Cost tier | premium | mid |
| Type | Consumer browser-agent extension (Chrome) — Anthropic | Google DeepMind browser-agent (research preview) |
| Created | 2025-08 | 2024-12 |
| Pricing | Bundled with Claude Max ($100-200/mo) | Bundled with Gemini Advanced ($19.99/mo) |
| Funding | Anthropic parent — $13.7B raised Sep-2025; ~$170B val | Google DeepMind parent (Alphabet) |
| Backend storage | Anthropic-managed session state; local extension storage | Google-managed session state |
| Deployment | Chrome extension (consumer side) + Anthropic cloud | Chrome extension + Google Cloud |
| API surface | Chrome extension UI; underlying API = Anthropic Messages | Chrome extension; underlying Gemini 2.0 API |
| Multi-tenancy | Single-tenant per Claude account | Single-tenant per Google account |
| MCP | Claude supports MCP servers (caller-side) | searched not found |
| A2A | searched not found | Google's own A2A protocol — likely first-party compatible |
| Optimised for | Letting Claude act inside the user's logged-in Chrome rather than a fresh sandbox | Gemini 2.0-powered Chrome agent |
| Anti-fit | Claude Max preview only; Chrome only; prompt-injection risk model still maturing | Research preview only; Chrome only; Gemini Advanced tier |
At a glance
| Claude for Chrome | Project Mariner | |
|---|---|---|
| Section | Computer-use & desktop agents | Computer-use & desktop agents |
| Tier | T1 | T1 |
| Type | Consumer browser-agent extension (Chrome) — Anthropic | Google DeepMind browser-agent (research preview) |
| Created | 2025-08 | 2024-12 |
| Pricing | Bundled with Claude Max ($100-200/mo) | Bundled with Gemini Advanced ($19.99/mo) |
| Funding | Anthropic parent — $13.7B raised Sep-2025; ~$170B val | Google DeepMind parent (Alphabet) |
| Backend storage | Anthropic-managed session state; local extension storage | Google-managed session state |
| Deployment | Chrome extension (consumer side) + Anthropic cloud | Chrome extension + Google Cloud |
| API surface | Chrome extension UI; underlying API = Anthropic Messages | Chrome extension; underlying Gemini 2.0 API |
| Multi-tenancy | Single-tenant per Claude account | Single-tenant per Google account |
| MCP | Claude supports MCP servers (caller-side) | searched not found |
| A2A | searched not found | Google's own A2A protocol — likely first-party compatible |
| OpenTelemetry | searched not found | searched not found |
| Optimised for | Letting Claude act inside the user's logged-in Chrome rather than a fresh sandbox | Gemini 2.0-powered Chrome agent |
| Anti-fit | Claude Max preview only; Chrome only; prompt-injection risk model still maturing | Research preview only; Chrome only; Gemini Advanced tier |
Taxonomy
| Axis | Claude for Chrome | Project Mariner |
|---|---|---|
| storage | kv | kv |
| retrieval | injection | injection |
| persistence | session | session |
| update | agent-controlled | agent-controlled |
| unit | turn | turn |
| governance | opaque | opaque |
| conflict | stateless | stateless |
Pros & cons
Claude for Chrome
Pros: First-party Anthropic agent inside the user's real browser; safety paper shipped at launch.
Cons: Claude Max preview only; Chrome-only; runs inside user's logged-in sessions (privacy surface).
Project Mariner
Pros: Strong WebVoyager numbers; Google distribution; A2A first-party adjacency.
Cons: Research preview; Chrome / Gemini Advanced tier; closed source.