> ## Documentation Index > Fetch the complete documentation index at: https://keystroke.ai/docs/llms.txt > Use this file to discover all available pages before exploring further. # Overview > Static context copied into the agent workspace. Files are static context you give an [agent](/docs/learn/agents/overview): documents, instructions, reference material that get copied into the agent's workspace so it can read them like local files. Use files for the background an agent needs every time, such as a product guide, a style sheet, or an API reference, that the agent should read rather than have packed into its system prompt. Use files for material the agent should read. Use [skills](/docs/learn/skills/overview) for instructions about how the agent should do a task. ## Example requests Ask your coding agent which reference material an agent should always have on hand. It can attach those documents as files. > "Give the sales agent our pricing sheet and competitor comparison to reference on every call prep." > "Attach our refund policy and support macros so the support agent can read them before drafting replies." ## How files work Files live in your project under `src/files/`, grouped into folders called file sets. Attach a set (or specific paths inside `src/files/`) with `sandbox: defineSandbox({ files })` on `defineAgent()`, and Keystroke materializes the contents into `/workspace/agent` before a prompt runs. ``` src/files/support/ product-guide.md support-instructions.md context/seed.txt ``` ```ts src/agents/support.ts theme={null} import { defineAgent } from "@keystrokehq/keystroke/agent"; import { defineSandbox } from "@keystrokehq/keystroke/sandbox"; export default defineAgent({ slug: "support", name: "Support", description: "Answers using the product guide in the agent file set.", systemPrompt: "Read /workspace/agent/product-guide.md before answering.", model: "xai/grok-4.5", sandbox: defineSandbox({ files: "support" }), }); ``` With `defineSandbox({ files: "support" })`, Keystroke copies `src/files/support/` into the agent workspace. The folder layout is preserved under `/workspace/agent`, so `src/files/support/context/seed.txt` becomes `/workspace/agent/context/seed.txt`. Point the agent at the paths it should read from the `systemPrompt`. You can also attach multiple sets, or only specific files under `src/files/` — see [Attach files to agents](/docs/learn/files/attach-files-to-agents). ## Files vs skills Files and [skills](/docs/learn/skills/overview) both materialize into the agent workspace, but they serve different purposes: | | Files | [Skills](/docs/learn/skills/overview) | | --------------------- | ------------------------------------------------------------------------------- | ------------------------------------- | | **What it is** | Static *context*: documents to read | A *playbook*: instructions for a task | | **Where it lands** | `/workspace/agent/{path}` | `/workspace/agent/skills/{slug}/` | | **Attach with** | `sandbox: defineSandbox({ files: "set" })` or `files: ["set", "other/file.md"]` | `skills: ["name"]` | | **Reach for it when** | The agent needs reference material | The agent needs procedural guidance | Many agents use both: files for the documents, a skill for how to use them. ## Files vs memory Files, the agent's own file system, and [memory](/docs/learn/agents/build-agents#memory) all involve "files," but they answer different questions: what *you* give the agent, what the agent *writes during a run*, and what the agent *remembers across runs*. | | Files (`src/files/`) | Agent file system (`/workspace`) | [Memory](/docs/learn/agents/build-agents#memory) | | ------------------ | ---------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------- | | **Who owns it** | You, authored in your project and version-controlled | The agent, during a run | The agent, written and recalled automatically | | **What it's for** | Static context the agent should read | `/workspace/agent` = shared across sessions (files/skills); `/workspace/session` = scratch, clones, installs | Carrying knowledge between sessions | | **Where it lives** | Seeded into `/workspace/agent/{path}` | `/workspace/agent` and `/workspace/session` | A memory area outside `/workspace` (`MEMORY.md`, `USER.md`, archived notes, searchable past sessions) | | **Lifetime** | Reconciled from your project on each prompt after deploy (add/update/delete) | Agent mount persists; session mount is per-session | Persists across sessions | The relationship in one line: **files** are the project-managed context you seed into the **agent file system**, while **memory** is the separate, durable store the agent uses to remember things from one session to the next. Because deployed files are reconciled from your project, treat them as managed input rather than a place the agent saves work. If an agent needs to remember something for next time, that's [memory](/docs/learn/agents/build-agents#memory), enabled by default and managed by the agent itself. Set `memory: false` on an agent to make it stateless. ## Files and the sandbox Files seed the agent's `/workspace/agent` directory — the **shared filesystem** (skills and deployed files). Keystroke tracks which paths came from your project and reconciles them on each prompt: * **Added** files appear on the next prompt after deploy * **Changed** files overwrite the previous deployed content (including agent edits to that path) * **Removed** files are deleted from `/workspace/agent` * Paths the agent creates on its own (not in your attachment) are left alone The agent system prompt lists every deploy-owned path under `/workspace/agent/`, and notes that other files written there persist across sessions and deploys. Treat `/workspace/agent` as shared context only — **not** a place to clone git repos or install packages (`node_modules`, Playwright browsers, etc.). Prefer `/workspace/session` for scratch, clones, and installs, and [memory](/docs/learn/agents/build-agents#memory) for knowledge that should survive across sessions. Details: [Sandboxes](/docs/learn/agents/build-agents#sandboxes). ## Next steps Attach sets, multiple sets, or specific files. Give agents reusable playbooks alongside files. Configure models, tools, skills, and files. How the agent workspace and file system work.