Runstack Agent
The workspace chat agent—attach files, add context, switch models, and manage conversations from the sidebar.
Source: https://runstack.engineer/docs/runstack-agent
Runstack Agent is the main workspace chat at /. It connects to your toolkits, external MCP servers, and published Studio agents so you can automate work in natural language.
Composer
Attach files
Click the + button in the prompt bar to attach files. Supported types:
- Images: JPEG, PNG, GIF, WebP
- Documents: PDF, plain text, CSV, Markdown
- Max size: 10 MB per file
Add context
Click the Context button (sliders icon) to toggle what the agent can use for a message:
| Option | Description |
|---|---|
| Firecrawl | Search the web and scrape pages for up-to-date answers (enabled by default) |
| Runstack KBrain | Inject knowledge base excerpts and workspace memory (configure under Settings → Knowledge Base) |
| MCP servers | Toggle individual external MCP servers for this message |
Use Manage knowledge base or Manage MCP servers in the context popover to open the matching workspace settings.
Mentions and slash commands
- Type
@to mention toolkits and search available tools - Type
/to invoke a published Studio agent by slash command
Placeholder: Ask Runstack to do anything | use @ for toolkits & / for agents
Models
In-chat model picker
Click the model selector in the prompt bar:
- Auto — Runstack picks the best model for the task (default)
- Turn off Auto to search and pick a specific model
- Models are grouped by provider: Cloudflare, OpenRouter, Google, Anthropic, OpenAI
- Capability badges: Tools, Reasoning
- Use the gear icon on a provider row to open LLM Providers settings for that provider
Your model choice is saved per workspace in browser storage.
LLM provider API keys
Go to Settings → Workspace → LLM Providers to bring your own keys:
- Toggle Show in chat per provider
- Enter API key (or Account ID + API token for Cloudflare)
- Add Custom models by model ID
- Save credentials, Test connection, or Clear your key
- Badges show Your key, Using Runstack, Included, or Bring your own key
This is separate from Settings → Workspace → API Keys, which are Runstack MCP/SDK execution keys.
External MCP servers
Add workspace-scoped MCP endpoints under Settings → Workspace → MCP Servers:
| Field | Description |
|---|---|
| Name | Display name in chat context |
| Server URL | MCP server endpoint |
| Authorization header | Optional auth token |
| Use in chat | Enable or disable per server |
Toggle servers on or off per message from the Context popover.
Messages
Assistant messages include action buttons:
| Action | Description |
|---|---|
| Copy | Copy message text to clipboard |
| Retry | Regenerate the assistant response |
| Download | Save the message as message-{id}.md |
| Token usage | Hover to see input and output token counts |
Web search sources
When Firecrawl runs, assistant messages show a N source(s) popover with favicons, titles, and hostnames for pages used in the answer.
Reasoning
When the model reasons, a collapsible Reasoned block appears with duration (e.g. 3.2s). Toggle visibility in Settings → Workspace → Appearance → Show Reasoned.
Tool call chain
Tool invocations render in one of two modes (configurable in Appearance settings):
| Mode | Description |
|---|---|
| List (default) | Collapsible list of individual tool calls with JSON input/output, running/completed/error states, and copy on code blocks |
| Compact pill | Single summary chip with tool icons — no per-call expansion |
The header shows {N} tool call(s) when collapsed.
Appearance settings
Settings → Workspace → Appearance:
| Setting | Default | Description |
|---|---|---|
| Show Reasoned | On | Show reasoning blocks in messages |
| Show token usage | On | Show token count on assistant messages |
| Toolcall UI | List | Switch to Compact pill for a denser tool display |
| Theme | System | System, Light, or Dark — press D to toggle |
Preferences are stored in browser localStorage.
Sidebar chats
Chats appear in the sidebar under Pinned, Recents, and Archive.
| Action | Description |
|---|---|
| Pin chat / Unpin chat | Keep important chats at the top |
| Archive / Unarchive | Move chats out of Recents into Archive |
| Rename | Change the chat title |
| Share | Copy a public link — anyone with the link can view without signing in |
| Delete | Permanently remove the chat and all messages |
Archived chats cannot be shared publicly — the Share action is hidden while a chat is archived.
Shortcuts
| Shortcut | Action |
|---|---|
| ⌘O / Ctrl+O | Start a New chat |
| ⌘K / Ctrl+K | Search workspace (chats, toolkits, pages) |
| D | Toggle theme |
Shared chat URLs follow the pattern /chat/share/{chatId}.