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write.file.host
Change any file the account can reach. Its effect is with-effort: undone at a cost.
What this id is made of
This is not a string. It is write.file.host, three nodes joined by three edges, and each of them has an address, a page and a JSON file. Follow any of them and you get the query for that word rather than a definition of it.
| Node | Edge | Reads as |
|---|---|---|
write | has_verb | this capability has the verb write |
file | acts_on | this capability acts on file |
host | reaches | this capability reaches host |
filesystem | in_family | this capability is in the filesystem family |
with-effort | has_undo_class | this capability has the undo class with-effort |
The gloss above is a convenience, not the definition. A node carries no inherent meaning: what
write.file.host is emerges from the edges traceable from it. The strongest case is host, where the deployment shapes that use it do not agree about what it means, and the page keeps the disagreement rather than averaging it.In 8 of 17 published shapes
| Deployment shape | Barrier there | Known by | Whose material | Note | |
|---|---|---|---|---|---|
| ● | Claude Code on the web (a remote session container) | none (not a control) | observed | not stated | a zero-byte file was created and removed in /etc: system configuration of the container is writable |
| ● | Claude Code (the CLI, on your own machine) | none (not a control) | derived | not stated | |
| ● | Claude Code (the CLI, on your own machine) | none (not a control) | derived | not stated | |
| ◐ | Claude Desktop (a desktop app with local tools) | setting (not a control) | derived | not stated | |
| ○ | The official Dropbox MCP server (contributed by riskmandate.ai) | boundary | documented | mixed | Copy "can recreate a deleted file or replace an existing file at the destination path"; Move renames or moves files and folders; CreateFile writes up to 5 MB of inline content. |
| ● | A scheduled job running as a service account | none (not a control) | derived | not stated | |
| ● | Actions runner (a hosted CI job) | none (not a control) | observed | not stated | the runner's user with passwordless escalation: every file on the ephemeral machine |
| ○ | The Google Workspace MCP servers (Gmail, Drive, Docs, Sheets, Slides, Calendar, Chat) (contributed by riskmandate.ai) | boundary | documented | mixed | drive.file creates new files or modifies files the user opened with the app; the Docs, Sheets and Slides servers each ask for the full write scope for their document type beside the read-only one. What "full" includes is open, below. |
| Barrier | What stands in the way | Is it a control | |
|---|---|---|---|
| ● | none | nothing in the way | no |
| ◉ | expectation | a rule in prose, enforced by nobody | no |
| ◐ | setting | a switch the agent's own account can flip | no |
| ○ | boundary | enforced above the grant, out of the agent's reach | yes |
What the starting mandates say about it
| The mandate says | Which mandates |
|---|---|
| authorised | none |
| refused | A coding assistant on my machine, The desktop app, with local tools switched on, Chat in the browser, nothing connected, A reader on my drive, Find and read my files, An assistant over my Workspace, reading |
| unstated | A coding assistant in a container on the web, Chat, with connectors switched on, A CI job on a hosted runner, A browser extension I installed, A scheduled job under a service account, A reader on my mailbox, Find things in the inbox, draft replies, never send, Search our tenant, read-only, A sandbox: build and run one AI-agent workflow, What the agent inferred it was authorised to do, from one session |
Unstated is not authorised. A mandate that never mentioned a capability did not authorise it, and the delta on every example page counts it as excess and says which kind it was.
What would move it to the fourth barrier
| What | What it costs | The barrier afterwards |
|---|---|---|
| the same container or account; the tool's own directory restriction is a setting anything running as you can step around | as above | boundary |
This is a published reduction, not a recommendation. Whether it is worth doing depends on the assets and the consequences, which are not in this document and are not this site's to guess. Since v0.4.3 it is also a node,
setting/write.file.host, in the deployment shape universe: it narrows this capability and moves it to the barrier named in the third column, which is the path the prohibitions table's last column is a projection of.