eve

--- title: "Project Layout" description: "Authored slots under agent/ and the path-derived naming rule." --- eve builds an agent by walking the filesystem under `agent/`. Each directory is an authored slot, and the slot a file lands in determines how eve loads it. ## Naming rule Identity comes from the path. You never write a `name` or `id` field on a `define*` call. | Path | Resolves to | | ------------------------------------- | --------------------- | | `agent/tools/get_weather.ts` | tool `get_weather` | | `agent/connections/linear.ts` | connection `linear` | | `agent/skills/summarize.md` | skill `summarize` | | `agent/subagents/researcher/agent.ts` | subagent `researcher` | The root agent takes its name from the enclosing `package.json` `name`, falling back to the app-root directory name when `package.json` has no `name`. A subagent takes its name from its directory. ## Recommended layout ```text my-agent/ ├── package.json ├── tsconfig.json ├── agent/ │ ├── agent.ts │ ├── instructions.md │ ├── instrumentation.ts │ ├── channels/ │ ├── connections/ │ ├── hooks/ │ ├── skills/ │ ├── lib/ │ ├── sandbox/ │ ├── tools/ │ ├── schedules/ │ └── subagents/ └── evals/ ``` Evals live in `evals/` at the app root, a sibling of `agent/`, not inside it. See [Evals](../evals/overview). ## Slot table The Subagents column states whether a local subagent (`subagents/<id>/`) can author the slot. A declared subagent inherits nothing from the root; it discovers its own slots. See [Subagents](../subagents). | Path | Description | Subagents | Notes | | ------------------------------------------------------- | ------------------------------------------- | --------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `agent.ts` | Runtime config | Yes | Model, modelOptions, compaction, build, experimental. See [Agent config](../agent-config). | | `instructions.md` / `instructions.ts` / `instructions/` | Base system prompt | Optional | A flat file, or a directory of `.md` and `.ts` files. Static sources compose at build time. Dynamic sources (`defineDynamic` + `defineInstructions`) resolve at runtime. Required on the root, optional on subagents. | | `instrumentation.ts` | Telemetry config | No | OTel exporter and AI SDK span settings, auto-discovered and run before agent code. Root-only. | | `channels/` | HTTP / messaging entrypoints | No | Root-only. | | `connections/` | External service connections (MCP, OpenAPI) | Yes | One connection per file; name derived from filename. | | `hooks/` | Lifecycle and stream-event subscribers | Yes | Module-backed only. Recursive directories supported. | | `skills/` | On-demand procedures and capability packs | Yes | Flat markdown, module-backed skills, or packaged skills. Seeded into `/workspace/skills/...`. | | `lib/` | Shared authored helper code | Yes | Import-only; not mounted into the workspace. | | `sandbox.ts` or `sandbox/sandbox.ts` | The agent's single sandbox | Yes | Use top-level `sandbox.ts` for a definition-only override; use `sandbox/sandbox.ts` + `sandbox/workspace/**` to also seed files. Framework default applies when neither is authored. | | `sandbox/workspace/**` | Files seeded into the sandbox | Yes | Mirrored into `/workspace/...` at session bootstrap. | | `tools/` | Typed executable integrations | Yes | Module-backed only. | | `schedules/` | Recurring jobs | No | Each schedule is `<name>.ts` (default-exported `defineSchedule`) or `<name>.md` (frontmatter `cron:` + prompt body). Recursive nesting supported. Root-only. | | `subagents/` | Specialist child agents | Yes | Each child is its own local package under `subagents/<id>/`. Nested subagents are supported. | ## What reaches the runtime workspace eve does not mount the whole tree. Only two sources land in the sandbox workspace: - `skills/` files → `/workspace/skills/...` - `agent/sandbox/workspace/**` → `/workspace/...` at session bootstrap Everything in `lib/` stays import-only source code and never reaches the workspace. ## Local subagent layout A local subagent lives under `subagents/<id>/` and uses the same `agent.ts` shape as the root. ```text agent/subagents/researcher/ ├── agent.ts ├── instructions.md ├── connections/ ├── hooks/ ├── skills/ ├── lib/ ├── sandbox/ ├── tools/ └── subagents/ ``` Rules: - `agent.ts` is required, and must declare a `description`. The parent reads it on the lowered subagent tool to decide when to delegate. - `instructions.md` / `instructions.ts` is optional (unlike the root agent, where it is required). - `connections/`, `hooks/`, `skills/`, `lib/`, `sandbox/`, and `tools/` are all supported, discovered from the subagent's own directory. - `channels/` and `schedules/` are not supported inside local subagents. - Nested subagents are supported. ## Flat layout Supported when the app root is also the agent root: ```text my-agent/ ├── package.json ├── agent.ts ├── instructions.md ├── tools/ └── skills/ ``` Prefer the nested layout. It keeps the app root separate from the authored surface. ## Why didn't eve discover my file? Run `eve info`. It lists the discovered surface and prints discovery diagnostics. From there, check that the file sits in the right authored slot (per the slot table above) and that the root-vs-subagent boundary is valid. eve also writes inspectable artifacts under `.eve/`. See the debugging artifacts in [instrumentation.ts](../guides/instrumentation) and the [CLI](./cli) reference. ## What to read next - [`agent.ts`](../agent-config): the runtime config at the root - [Tools](../tools): the most common authored slot - [TypeScript API](./typescript-api): the define\* helpers and where they import from