# Reconnect to session sandbox

Source: https://recoupable.dev/docs/api-reference/sandbox/reconnect

Reconnect to session sandbox

## GET /api/sandbox/reconnect

Full OpenAPI specification: https://recoupable.dev/docs/spec/sandbox.json

## Authentication

This operation requires one of the security alternatives in the specification below. Security scheme definitions are included where present in the published specification.

[Authentication guide](https://recoupable.dev/docs/authentication)

## Operation and referenced schemas

```json
{
  "openapi": "3.1.0",
  "info": {
    "title": "Recoup API - Session Sandboxes",
    "description": "Per-session sandbox lifecycle for agent runs. These endpoints provision, restore, and report status on the Sandbox bound to a single agent session. Distinct from the legacy `/api/sandboxes` (plural) account-scoped endpoints — these are session-scoped and used by the open-agents-style chat UI to drive the \"loading sandbox…\" state on session entry.",
    "license": {
      "name": "MIT"
    },
    "version": "1.0.0"
  },
  "servers": [
    {
      "url": "https://api.recoupable.dev"
    }
  ],
  "security": [
    {
      "ApiKeyAuth": []
    },
    {
      "BearerAuth": []
    }
  ],
  "paths": {
    "/api/sandbox/reconnect": {
      "get": {
        "summary": "Reconnect to session sandbox",
        "description": "Live runtime probe for the sandbox bound to a session. Unlike `GET /api/sandbox/status` (DB-only read), this endpoint actually runs a quick command inside the sandbox to verify it is reachable. Used by the chat UI on session re-entry / tab refocus to decide whether to flip out of \"loading sandbox…\" or surface a \"resume\" affordance. Returns one of three operational outcomes via the `status` field: `\"connected\"` (sandbox is alive, included `expiresAt` reflects current expiry), `\"expired\"` (the runtime state is gone — the UI should offer to resume from snapshot if `hasSnapshot` is true, otherwise create a fresh sandbox), or `\"no_sandbox\"` (no sandbox has been provisioned for this session yet).",
        "parameters": [
          {
            "name": "sessionId",
            "in": "query",
            "required": true,
            "description": "The id of the session whose sandbox to reconnect to.",
            "schema": {
              "type": "string"
            }
          }
        ],
        "responses": {
          "200": {
            "description": "Reconnect probe completed. Inspect `status` for the outcome.",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/ReconnectResponse"
                }
              }
            }
          },
          "400": {
            "description": "Missing `sessionId` query parameter.",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/Error"
                }
              }
            }
          },
          "401": {
            "description": "Unauthorized — invalid or missing API key / Bearer token.",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/Error"
                }
              }
            }
          },
          "403": {
            "description": "Forbidden — the authenticated account does not own this session.",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/Error"
                }
              }
            }
          },
          "404": {
            "description": "Not found — no session exists with the given `sessionId`.",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/Error"
                }
              }
            }
          }
        }
      }
    }
  },
  "components": {
    "schemas": {
      "ReconnectResponse": {
        "type": "object",
        "required": [
          "status",
          "hasSnapshot",
          "lifecycle"
        ],
        "properties": {
          "status": {
            "type": "string",
            "enum": [
              "connected",
              "expired",
              "no_sandbox"
            ],
            "description": "`connected` when the live runtime probe succeeded; `expired` when the recorded runtime state is no longer reachable (the UI should offer resume-from-snapshot or fresh-create); `no_sandbox` when the session has never had a sandbox provisioned."
          },
          "hasSnapshot": {
            "type": "boolean",
            "description": "True when a paused/snapshotted sandbox exists and can be resumed. Used by the UI to decide whether to show \"resume\" vs \"create\" affordances on `expired` / `no_sandbox`."
          },
          "expiresAt": {
            "type": "integer",
            "format": "int64",
            "description": "Epoch milliseconds when the sandbox runtime will expire. Present only when `status` is `\"connected\"`; reflects the freshly-probed expiry, which may differ from `lifecycle.sandboxExpiresAt` if the sandbox extended itself between writes."
          },
          "lifecycle": {
            "$ref": "#/components/schemas/SandboxLifecycle"
          }
        }
      },
      "Error": {
        "type": "object",
        "required": [
          "status",
          "error"
        ],
        "properties": {
          "status": {
            "type": "string",
            "enum": [
              "error"
            ],
            "description": "Always `\"error\"` for error responses."
          },
          "error": {
            "type": "string",
            "description": "Human-readable error message."
          }
        }
      },
      "SandboxLifecycle": {
        "type": "object",
        "required": [
          "serverTime",
          "state",
          "lastActivityAt",
          "hibernateAfter",
          "sandboxExpiresAt"
        ],
        "description": "Lifecycle envelope shared between `GET /api/sandbox/status` and `GET /api/sandbox/reconnect`. Server-clock-stamped snapshot of the sandbox's lifecycle FSM state and the timestamps the UI uses to render countdown timers.",
        "properties": {
          "serverTime": {
            "type": "integer",
            "format": "int64",
            "description": "Server's current epoch milliseconds. Use this — not the client clock — when computing how much time is left before `hibernateAfter` or `sandboxExpiresAt`."
          },
          "state": {
            "type": "string",
            "nullable": true,
            "enum": [
              "provisioning",
              "active",
              "hibernating",
              "hibernated",
              "restoring",
              "archived",
              "failed"
            ],
            "description": "Lifecycle FSM state. `null` for sessions that have never had a sandbox."
          },
          "lastActivityAt": {
            "type": "integer",
            "format": "int64",
            "nullable": true,
            "description": "Epoch milliseconds of the last recorded sandbox activity, or null if there has been none."
          },
          "hibernateAfter": {
            "type": "integer",
            "format": "int64",
            "nullable": true,
            "description": "Epoch milliseconds after which the sandbox is eligible for hibernation, or null when not applicable."
          },
          "sandboxExpiresAt": {
            "type": "integer",
            "format": "int64",
            "nullable": true,
            "description": "Epoch milliseconds when the sandbox runtime expires, or null when not applicable."
          }
        }
      }
    },
    "securitySchemes": {
      "ApiKeyAuth": {
        "type": "apiKey",
        "in": "header",
        "name": "x-api-key"
      },
      "BearerAuth": {
        "type": "http",
        "scheme": "bearer"
      }
    }
  }
}
```