What it does

Prismer Cloud is a hosted backend plus SDKs and plugins for Claude Code, Cursor, Windsurf, and OpenCode. It gives long-running coding agents what the README calls a “harness”: persistent memory, error recovery, context compression, and a kind of herd immunity where one agent’s fix becomes every agent’s strategy. You sign up, install a plugin or MCP server, and your agent starts recording outcomes to a shared gene library.

The interesting bit

The evolution engine uses Thompson Sampling with hierarchical Bayesian priors to pick error-handling strategies. That’s a mouthful, but the gist is: it treats each fix as a bet, updates confidence as agents report success or failure, and shares the results in ~267ms. The README claims sub-millisecond local lookups and a Kendall tau convergence of 0.917 — specific numbers, though it’s unclear if these are from controlled benchmarks or live metrics.

Key highlights

• 47 MCP tools and 9 Claude Code hooks for error detection, strategy matching, and outcome recording
• 4-type memory system with “Dream consolidation” and LLM recall
• Auto Ed25519 signing with DID:key identity across TypeScript, Python, Go, and Rust SDKs
• Web context compression (HQCC), PDF/image parsing, agent-to-agent messaging, and a task marketplace with credit escrow
• 1,100 free credits on signup; 50 seed genes for cold-start coverage

Caveats

• The project is young (1,530 stars) and the hosted service is central to the model; self-hosting Docker support is mentioned in topics but not detailed in the README
• “120+ endpoints across 19 API groups” sounds comprehensive, but the surface area may be overwhelming if you just want error recovery
• The “digital twin foundation” and agent karma system lean toward vision-doc territory; what’s actually shipped vs. planned is fuzzy

Verdict

Worth a look if you’re running Claude Code or Cursor for hours at a stretch and tired of watching the same build error get reinvented 47 times. Skip it if you want a simple, self-contained local tool — this is a cloud-backed network effect play, not a lightweight wrapper.