Research MCP Server | Caesar | API Documentation

The Research MCP server is a hosted MCP endpoint that lets MCP-aware clients call Caesar’s API-key authenticated research endpoints as tools. It is distinct from the Docs MCP server, which only answers documentation questions.

Looking for documentation search? See the MCP Docs Server.

Server URL

https://api.caesar.xyz/mcp

Authentication

Pass your Caesar API key as a Bearer token in the Authorization header.

Authorization: Bearer csk-...

Setup

OpenCode

Add the research MCP server to your OpenCode config under mcp (see the OpenCode MCP docs):

opencode.json

1 {
2   "$schema": "https://opencode.ai/config.json",
3   "mcp": {
4     "caesar-research": {
5       "type": "remote",
6       "url": "https://api.caesar.xyz/mcp",
7       "headers": {
8         "Authorization": "Bearer ${CAESAR_API_KEY}"
9       },
10       "enabled": true
11     }
12   }
13 }

Set your API key in the environment:

$ export CAESAR_API_KEY=csk-...

Cursor

Add a remote MCP server in mcp.json (see Cursor MCP docs):

mcp.json

1 {
2   "mcpServers": {
3     "caesar-research": {
4       "url": "https://api.caesar.xyz/mcp",
5       "headers": {
6         "Authorization": "Bearer ${env:CAESAR_API_KEY}"
7       }
8     }
9   }
10 }

Set your API key in the environment:

$ export CAESAR_API_KEY=csk-...

Claude Code

Use the CLI to add the remote HTTP server with your API key (see Claude Code MCP docs):

$ claude mcp add --transport http caesar-research https://api.caesar.xyz/mcp \
>   --header "Authorization: Bearer $CAESAR_API_KEY"

Set your API key in the environment before running the command:

$ export CAESAR_API_KEY=csk-...

Codex

Add the server in ~/.codex/config.toml (see Codex MCP docs):

config.toml

1 [mcp_servers.caesar_research]
2 url = "https://api.caesar.xyz/mcp"
3 bearer_token_env_var = "CAESAR_API_KEY"

Set your API key in the environment:

$ export CAESAR_API_KEY=csk-...

Droid

Add the HTTP server with the CLI (see Droid MCP docs):

$ droid mcp add caesar-research https://api.caesar.xyz/mcp --type http \
>   --header "Authorization: Bearer $CAESAR_API_KEY"

Set your API key in the environment before running the command:

$ export CAESAR_API_KEY=csk-...

Tools

The MCP server mirrors the existing research endpoints and exposes them as tools.

Research jobs

Tool	Endpoint
`research_create`	`POST /research`
`research_list`	`GET /research`
`research_get`	`GET /research/{id}`
`research_brainstorm`	`POST /research/brainstorm`

Files & collections

Tool	Endpoint
`research_file_upload`	`POST /research/files`
`research_files_list`	`GET /research/files`
`research_result_content`	`GET /research/{id}/results/{resultId}/content`
`research_collections_create`	`POST /research/collections`
`research_collections_list`	`GET /research/collections`
`research_collections_get`	`GET /research/collections/{id}`
`research_collections_patch`	`PATCH /research/collections/{id}`

Chat & updates

Tool	Endpoint
`research_chat_list`	`GET /research/{id}/chat`
`research_chat_create`	`POST /research/{id}/chat`
`research_chat_message_get`	`GET /research/{id}/chat/{message_id}`
`research_chat_stream`	`GET /research/{id}/chat/{message_id}/stream`
`research_events_stream`	`GET /research/{id}/events`
`research_update_create`	`POST /research/{id}/updates`
`research_updates_list`	`GET /research/{id}/updates`

File uploads

Use research_file_upload with base64-encoded content:

1 {
2   "file_name": "report.pdf",
3   "content_base64": "...",
4   "content_type": "application/pdf",
5   "collection_id": "<optional-uuid>"
6 }

API version override (optional)

Every tool accepts an optional api_version argument to set the API-Version header when calling the underlying endpoint.