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One workspace all your AI agents can read and write

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A vnsh workspace: an incident report shared as one link, rendered from markdown, editable by any agent holding it

--- Right now you paste the same context into Claude Code, then Cursor, then Slack. vnsh gives that context one address instead. Drop it once and get a link; every agent and every person you hand it to opens the **same living document**, and can change it. Encrypted in your browser before upload, so vnsh never sees it, and deleted 24 hours after the last edit. ```bash kubectl logs pod/app | vn # https://vnsh.dev/w/k2p9xf...#w=... edit link — read and write # https://vnsh.dev/w/k2p9xf...#r=... view-only — read, never write ``` ## Why this and not a pastebin A pastebin gives you a snapshot. A workspace has a stable address and a version, so the next agent writes back to the same place instead of starting a new one. Two properties make that safe to share: - **The server cannot read it.** Content is encrypted client-side and the key rides in the URL fragment, which HTTP never transmits. What the server stores is ciphertext and a SHA-256 of a write token — not the token. The file's name is encrypted too, under the same key, so your recipient downloads `analysis.py` while vnsh holds a string it cannot decode. That is checkable from outside: forge a token and you get a 403. - **Two agents cannot silently clobber each other.** Writes are conditional on the version you read. An unconditional write is refused outright; a stale one gets a 412 telling you to re-read and merge. Measured in production with five concurrent writers: one succeeded, four were told, nothing was lost. ## Get started ### For an agent — the point of the thing Paste this into Claude Code, Cursor, OpenHands, Cline, Windsurf, Zed — anything that speaks MCP: ``` Set up vnsh workspaces — one link to hand work between people and agents: https://vnsh.dev/llms.txt ``` It reads the protocol, installs the MCP server, and writes a standing rule into its own instruction file so it keeps using workspaces afterwards. By hand instead: ```bash claude mcp add vnsh -- npx -y vnsh-mcp@1.9.0 ``` The server exposes `vnsh_artifact_create`, `vnsh_artifact_list`, `vnsh_artifact_read`, `vnsh_artifact_update`, `vnsh_workspace_create`, `vnsh_workspace_read`, `vnsh_workspace_update`, `vnsh_workspace_history`, `vnsh_workspace_restore`, `vnsh_workspace_renew` and `vnsh_workspace_open`, plus `vnsh_share`, `vnsh_share_file` and `vnsh_read` for one-shot content. ### From the terminal ```bash npx vnsh # or: npm i -g vnsh # or: curl -sL vnsh.dev/i | sh (one-shot links only) vn ./report.html # create a workspace from a file git diff | vn # or from stdin vn read "" # read one back — workspace, public, or legacy blob vn write "" ./new # replace the contents; refuses to clobber vn history "" # list the latest 20 retained versions vn restore "" 3 # restore v3 as a new latest version vn init . # teach agents in this project to use vnsh ``` `vn init` adds an idempotent managed section to the project's agent instruction file. It works across agent vendors and records only an anonymous "project initialized" dimension when that CLI later creates a workspace, so the experiment can be measured without collecting a project name or path. `--public` publishes it unencrypted (see below). `--blob` explicitly makes a one-shot link. `--ttl` works for workspaces too, up to 168 hours; subsequent writes preserve that lifetime, and `vn renew` can extend it without an edit. The dependency-free shell function from `curl -sL vnsh.dev/i | sh` handles one-shot links only. Workspaces need HKDF-SHA256 and AES-256-GCM, and the openssl that ships with macOS is LibreSSL, which has neither — it hands `/w/` links to `npx vnsh` when Node is available and says so plainly when it is not. ### From a browser — drop a file or paste, and get both links back. Nothing is uploaded before it is encrypted. ### From CI [`upload-to-vnsh`](https://github.com/raullenchai/upload-to-vnsh) uploads build output or failing test logs and prints a link in the job summary. ### From Chrome The [extension](extension/) previews vnsh links inline on GitHub, Slack and Discord, and bundles a screenshot, console errors and the page URL into one link with ⌘D. ## The three kinds of link | Link | Carries | Who can read | Who can write | |---|---|---|---| | `vnsh.dev/w/{id}#w=` | the root secret | anyone with the link | anyone with the link | | `vnsh.dev/w/{id}#r=` | the content key | anyone with the link | **nobody** | | `vnshcontent.dev/p/{id}` | nothing | anyone at all | only the author's `#w=` link | The view-only tier is not a setting the server enforces — it is arithmetic. The content key is `HKDF(secret, "vnsh/enc/v2")`, a one-way derivation, so its holder can decrypt every version while being unable to recover the secret and therefore unable to derive a write token. **Public workspaces** exist because a person opening a link has a browser doing the decryption for them, and an agent's `fetch` does not. A public workspace is stored as written and served as an ordinary document, so anything that speaks HTTP can read it with no key and no setup. The trade is stated where you choose it: **vnsh can read a public workspace.** It is never the default and never inferred, its visibility is fixed at creation, and changing it still requires the write token. They are served from **`vnshcontent.dev`**, a separate registrable domain, and that is not cosmetic. A public document is written by a stranger and rendered as a top-level page, while reputation systems — Safe Browsing, mail gateways, corporate proxies — list a domain rather than a path. One abusive page on `vnsh.dev` would take the API, the site and every installed CLI, MCP server and extension down with it. A subdomain would not help; the unit is the registrable domain. Sandboxing is a separate matter and already handled: a public document is served with a `sandbox` CSP directive, so it loads into an opaque origin with no cookies, no storage, no network and no access to any other page. `/w/` links stay on `vnsh.dev` because the key in the fragment is a real gate — the server has never seen their plaintext and neither can a crawler. Don't assemble a public URL yourself. Creating one returns the exact link in the response's `url` field, which is also what keeps a self-hosted single-domain instance working. ## How it works ``` you ──encrypt──▶ [ vnsh: ciphertext, no key ] ──decrypt──▶ agent / person │ deleted 24h after the last write ``` **Key schedule** ``` S = random(32) root secret, lives only in the fragment K = HKDF-SHA256(S, "vnsh/enc/v2") content key — AES-256-GCM W = HKDF-SHA256(S, "vnsh/write/v2") write token, sent as 64 hex chars H = SHA-256(W) the only derived value the server stores ``` Workspaces use **AES-256-GCM**, not the AES-256-CBC of one-shot blobs, because mutable content needs integrity: without an authentication tag, anyone able to rewrite storage — the host included — could flip ciphertext bits undetectably, which hollows out the whole guarantee. Nonces are random per write and prepended, never derived from a version number. The viewer renders HTML and markdown in a frame with `sandbox="allow-scripts"` and deliberately no `allow-same-origin`, so content runs in an opaque origin and cannot read the key out of `location.hash`; an injected `default-src 'none'` removes its network access. The whole protocol is specified in [`/llms.txt`](https://vnsh.dev/llms.txt), creation included, so you can implement it in any language with a crypto library and run no vnsh code at all. Someone did, in about 200 lines. ## API | Endpoint | Purpose | |---|---| | `POST /api/workspace` | Create. Requires `X-Vnsh-Write-Hash`; `X-Vnsh-Public: 1` to publish. Returns `url` when public. | | `GET /api/workspace/:id` | Read ciphertext. `ETag` is the version. | | `PUT /api/workspace/:id` | Replace. Requires `X-Vnsh-Write` and `If-Match`. | | `GET /w/:id` | The viewer. Decrypts client-side, renders sandboxed. | | `GET /p/:id` | A public workspace, as a plain document — on `vnshcontent.dev`. | | `POST /api/drop` | One-shot blob (v1). `?ttl=` and `?price=`. | | `GET /api/blob/:id` | Read a one-shot blob. | | `GET /llms.txt` | The protocol, written for agents. | Writes answer `428` without `If-Match`, `412` on a stale version, and `403` on a bad write token. Full reference in [`docs/api.md`](docs/api.md). ## Security model ### Accounts and permanent artifacts Anonymous sharing remains account-free and temporary. Sign in at `https://account.vnsh.dev` with a magic link to keep newly created workspaces and `/artifact/` pages until you delete them. Browser creates use the signed-in session automatically. For the CLI, run `vn login` and approve the device in your browser. MCP and CI can use an account token in `VNSH_TOKEN`; content is still encrypted locally for capability-link workspaces, and the account database stores only their ownership metadata, not keys or plaintext. During the free preview, each account can keep 100 documents and 1 GB total, including retained versions. Keep the returned link: its fragment is the only copy of the decryption/editing secret, so the account can manage retention and deletion but cannot recover a lost key. Phase 1 account Artifacts add a separate collaboration mode: authenticated humans and Agent tokens can discover and version private Artifact content without carrying a fragment key. That convenience has a different security boundary—vnsh can technically read account Artifact content. It is never silently substituted for an anonymous encrypted workspace, and only a human may approve or publish by default. ```sh vn login vn artifact create report.md --title "Release report" --type report vn artifact list --query release --status draft vn artifact read vn artifact update report.md --base-version 1 --change-summary "Verified production" ``` Add `--json` to any Artifact command when another program or Agent will consume the result. **What holds.** vnsh cannot read encrypted content, cannot write to it, and cannot recover a write token from anything it stores. Rendered content runs with no same-origin access and no network, so a hostile document can neither reach the key nor send anything anywhere. **What does not.** - **Handing someone a link hands them the key**, including that agent's model provider. The 24-hour clock is what bounds this, not the encryption — and each write restarts it, so a workspace edited daily stays alive. - **The boundary is the client, not the transport.** Whatever encrypts holds your plaintext first, and the MCP server and CLI both do. `npx -y` refetches the latest published version on every start; pin it (`vnsh-mcp@1.9.0`), install it globally once, or build from source if you review what you run. - **A public workspace is readable by vnsh**, by design. That is the tier. - **Metadata is not private.** Times, sizes and addresses exist for any hosted service. Only the content does not. ## Self-hosting Cloudflare Workers plus an R2 bucket. No database, no KV. ```bash git clone https://github.com/raullenchai/vnsh.git cd vnsh/worker && npm install wrangler r2 bucket create vnsh-store wrangler deploy ``` `wrangler.toml` binds R2, two native rate limiters and an Analytics Engine dataset. Earlier versions used a KV namespace for metadata and counters; it was removed after the free-tier write cap took the whole site down, and nothing needs it now — if you are following an older guide that tells you to create one, you do not. See [`docs/self-hosting.md`](docs/self-hosting.md). ## Repository | Path | What it is | |---|---| | `worker/` | Cloudflare Worker: API, viewer, homepage, `llms.txt` | | `mcp/` | `vnsh-mcp` — the MCP server agents use | | `cli/npm/` | `vnsh` — the `vn` command | | `cli/` | `install.sh` and the dependency-free shell function | | `extension/` | Chrome extension | | `docs/` | Architecture, API, CLI, MCP, operations, self-hosting | | `docs/plans/` | Design documents, including the v2 workspace plan | ```bash npm test # every package cd worker && npm run dev # local worker ``` Four packages carry their own copy of the key schedule, because they ship independently. Each is pinned to the same test vectors: a link made by one that will not open in another reads as corruption rather than version skew, so the failure would be silent. If you change a derivation, those tests are what stops that happening quietly. ## Contributing Issues and pull requests welcome, including the ones that tell us we are wrong — the most useful contribution so far was someone reimplementing the protocol from `llms.txt` and reporting everything the document had failed to say. Start with [CONTRIBUTING.md](CONTRIBUTING.md). It covers the two traps in this codebase that catch everyone: the worker's client-side code lives inside a template literal, so backslashes must be doubled and a stray backtick ends the string a hundred lines from where the compiler complains. Found a security issue? Please do not open a public issue — [SECURITY.md](SECURITY.md) has the private form, and lists what is claimed and what is deliberately not. ## License MIT — see [LICENSE](LICENSE).

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