Chaser Documentation

Chaser exposes an MCP-compatible JSON-RPC endpoint for AI agent integration. Use it to give agents access to sandbox environments, browser automation, and workspace management through a standard tool interface.

Endpoint

POST /v1/mcp
Authorization: Bearer <api_key>
Content-Type: application/json

Both user API keys and service account API keys can authenticate to this endpoint.

Local stdio bridge

If your agent expects a local stdio MCP server, use the CLI bridge:

$ # install binary (either path works)
$ npm i -g chaser-cli
$ # or
$ npx chaser-mcp --help
$ 
$ # keep auth in env (not in agent config files)
$ export CHASER_API_KEY=\"sk_your_key_here\"
$ export CHASER_API_URL=\"https://api.chaser.sh\"
$ 
$ # run bridge directly
$ chaser mcp serve

Install config entries for supported agents:

$ chaser mcp install --agent all
$ chaser mcp doctor --agent all

Supported methods

Method	Description
`initialize`	Initialize the MCP session
`ping`	Health check
`notifications/initialized`	Client initialization notification
`tools/list`	List available tools
`tools/call`	Call a tool

High-level tools

These are the recommended starting points for agent integration:

`terminal`

Run shell commands and perform structured file operations in a sandbox. Auto-provisions or reuses a session when session_id is omitted.

Parameters:

Parameter	Type	Description
`session_id`	string	Target a specific session (optional)
`workspace`	string	Workspace name or ID (optional)
`ephemeral`	boolean	Use a disposable session (optional)
`image`	string	OCI image for ephemeral sandboxes (optional)
`command` / `cmd`	string	Shell command to run
`xml`	string	Structured file operation (`read_file`, `write_file`, `apply_edit`, `list_files`)
`timeout_ms`	number	Execution timeout in milliseconds

$ curl -sS "$CHASER_API_URL/v1/mcp" \
>   -H "Authorization: Bearer $CHASER_API_KEY" \
>   -H "Content-Type: application/json" \
>   -d '{
>     "jsonrpc": "2.0", "id": 1,
>     "method": "tools/call",
>     "params": {
>       "name": "terminal",
>       "arguments": {
>         "workspace": "my-project",
>         "command": "git status && ls /workspace"
>       }
>     }
>   }' | jq

`browser`

Browser automation backed by an auto-provisioned or reused browser session, driven through chrome-devtools-mcp.

Parameters:

Parameter	Type	Description
`session_id`	string	Target a specific session (optional)
`workspace`	string	Workspace name or ID (optional)
`ephemeral`	boolean	Use a disposable session (optional)
`action`	string	`prepare`, `discover`, or `call`
`method`	string	Browser tool method name (required for `action=call`)
`params`	object	Arguments for the browser tool (for `action=call`)
`timeout_ms`	number	Execution timeout in milliseconds

$ curl -sS "$CHASER_API_URL/v1/mcp" \
>   -H "Authorization: Bearer $CHASER_API_KEY" \
>   -H "Content-Type: application/json" \
>   -d '{
>     "jsonrpc": "2.0", "id": 1,
>     "method": "tools/call",
>     "params": {
>       "name": "browser",
>       "arguments": {"ephemeral": true, "action": "prepare"}
>     }
>   }' | jq

Lifecycle and utility tools

For explicit control over sessions and workspaces:

Tool	Description
`chaser_list_sessions`	List sessions in the active account
`chaser_get_session`	Get session details by ID
`chaser_create_browser_session`	Create a browser session
`chaser_create_sandbox_session`	Create a sandbox session
`chaser_terminate_session`	Terminate a session
`chaser_exec_sandbox`	Execute a command in a sandbox
`chaser_self_test_sandbox`	Run runtime diagnostics
`chaser_get_sandbox_forward_url`	Get a port forwarding URL
`chaser_list_workspaces`	List workspaces
`chaser_get_workspace`	Get workspace details
`chaser_delete_workspace`	Delete a workspace
`chaser_bulk_delete_workspaces`	Bulk delete workspaces
`chaser_set_workspace_name`	Rename a workspace

User-only tools

These tools are available only to human user principals (not service accounts):

Tool	Description
`chaser_request_assistant_config_change`	Propose an assistant config change
`vault_set`	Store a credential in the vault
`vault_delete`	Remove a credential
`vault_list_keys`	List vault credential keys

Dynamic MCP tools

Workspace-defined MCP servers can expose additional tools:

Tool	Description
`mcp_call`	Call a workspace-defined MCP tool
`mcp_discover`	Discover tools from a workspace MCP server

The assistant_id parameter on mcp_call/mcp_discover is only supported for user principals (for assistant-scoped vault injection).

Compatibility

chaser_sa3p_execute is still accepted for backward compatibility but new integrations should use terminal.

Service account access

Service account API keys receive the account-scoped infrastructure tool catalog. They can use terminal, browser, all lifecycle/utility tools, and mcp_call/mcp_discover. They cannot access assistant config-change or vault tools.

CHASM

CHASM assistants use this same MCP surface internally. Chaser handles authentication on behalf of signed-in product users, so assistants do not need a separate API key.

List available tools

$ curl -sS "$CHASER_API_URL/v1/mcp" \
>   -H "Authorization: Bearer $CHASER_API_KEY" \
>   -H "Content-Type: application/json" \
>   -d '{"jsonrpc": "2.0", "id": 1, "method": "tools/list"}' | jq