Capacities MCP Bridge (Unofficial)
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@Capacities MCP Bridge (Unofficial)save this link to my daily notes: https://example.com"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.

Unofficial Capacities.io MCP Tools
Disclaimer
This project provides several methods for connecting to the Capacities note taking app API using the Model Context Protocol (MCP). It was 100% vibe-coded with the help of Gemini 2.5 Pro. While it works, it relies on third-party adapter services and, in some cases, your own hosting. Use at your own risk.
For everyone looking for a native Bun implementation, there exists another project https://github.com/jem-computer/capacities-mcp
Related MCP server: Fastidious MCP Server
Table of Contents
Setup for Claude Desktop (with Node.js Bridge)
Use this if you need to connect Claude Desktop and it requires simple tool names.
Setup for Simple SSE Clients (CLion, VS Code)
Use this for a direct connection from a compatible IDE plugin.
Advanced Setup for Genspark (Self-Hosted Server)
The most reliable and robust method. Use this for Genspark or any other client if you have your own server/VPS.
General Prerequisites
A Capacities API Token. You can generate this from your Capacities account settings if you have a paid account.
The MCP Link Generator tool: https://mcp-link.vercel.app/
Setup 1: Claude Desktop (with Node.js Bridge)
This method uses the included capacities-claude-bridge.js script to act as a translator between Claude Desktop (which needs simple tool names) and the MCP adapter (which creates complex names).
Step 1.1: Install Node.js and Download Files
Install Node.js: Go to the official Node.js website and download and install the LTS version for your operating system.
Download the Bridge Code: Open a terminal (like Git Bash, Command Prompt, or PowerShell) and run the following commands:
# Clone the repository to a permanent location git clone https://github.com/natkitten/capacities-mcp-bridge-unofficial.git # Navigate into the project folder cd capacities-mcp-bridge-unofficialInstall Dependencies: While inside the
capacities-mcp-bridge-unofficialfolder, run:npm install
Step 1.2: Generate the Server URL for the Bridge
Go to mcp-link.vercel.app.
Fill in the form:
OpenAPI Specification URL: Use this specific URL for the Claude bridge setup. It uses snake_case
operationIds.https://gist.githubusercontent.com/natkitten/e6ce1335c2cdad87a9237156c5cda315/raw/capacities_openapi_2.jsonAPI Base URL:
https://api.capacities.ioHTTP Headers: Enter your Authorization header:
Authorization: Bearer YOUR_CAPACITIES_API_TOKENPath Filters: Leave this field completely empty.
Encoding Options: Select "Base64 (JSON Encoded)".
Click "Generate MCP Link" and copy the resulting URL.
Step 1.3: Configure the Bridge Script
Open the
capacities-claude-bridge.jsfile (located in the folder you just downloaded) in a text editor.Paste the URL you just copied, replacing the placeholder text for the
SSE_URLconstant.const SSE_URL = 'https://mcp-openapi-to-mcp-adapter.onrender.com/sse?code=...'; // YOUR URL HERESave the file.
Step 1.4: Configure Claude Desktop (Windows)
Open File Explorer and navigate to your Claude Desktop config file by pasting this path into the address bar:
%APPDATA%\Claude Desktop\claude_desktop_config.jsonOpen the file and add the
mcp_bridgessection as shown below.{ "mcpServers": { "capacities": { "command": "node", "args": ["C:\\path\\to\\your\\capacities-mcp-bridge-unofficial\\capacities-claude-bridge.js"] } } }CRUCIAL: Replace
C:\\path\\to\\your\\capacities-mcp-bridge-unofficialwith the actual, absolute path to the folder where you cloned the repository. Remember to use double backslashes\\.Save the
claude_desktop_config.jsonfile and restart Claude Desktop.
Capacities API at a glance
Endpoint | What it does | Typical use-case |
| Lists all Capacities spaces the token can access | Show a picker or verify the token |
| Returns structures, collections & property definitions of a space | Needed once at startup to map IDs to human labels |
| Full-text or title search across one or many spaces | Let the LLM find existing notes before it creates new ones |
| Saves an external URL (and optional tags/markdown) into a space | Quick bookmarking from chat |
| Appends Markdown to today’s daily note in a space | Fast journaling / meeting-note dump |
Current rate-limits (per user / 60 s window):
/spaces&/space-info: 5 requests/search: 120 requests/save-weblink: 10 requests/save-to-daily-note: 5 requests
For everything else (errors, structures, OpenAPI spec), see the official docs ➜ https://api.capacities.io/docs/.
https://github.com/user-attachments/assets/257aada5-5f65-4aec-b7da-4766452e3cb5
Setup 2: Simple SSE for IDEs (Cline/RooCode in VS Code)
This method is for MCP plugins that can handle the mcplink_... tool names directly. No bridge script is needed.
Follow Step 1.2 above to generate your unique Server URL from
mcp-link.vercel.app, using thecapacities_openapi_2.jsonand leaving "Path Filters" empty.Find the MCP configuration file for your IDE. It's often located at
YOUR_HOME_DIRECTORY/.mcp/servers.json.Add the following entry, replacing the placeholder with your generated URL:
{ "servers": { "capacities": { "url": "PASTE_YOUR_GENERATED_URL_HERE" } } }Restart your IDE. The tools should appear with their full
mcplink_...names.
Setup 3: Advanced Self-Hosted Server for Genspark
This is the most reliable method. It runs the MCP server on your own VPS. This setup requires a slightly different OpenAPI spec to work around a parser bug in the self-hosted server package.
Step 3.1: VPS and Node.js Setup
Connect to your VPS via SSH (
ssh root@YOUR_VPS_IP).Install
nvm(Node Version Manager):curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.7/install.sh | bashActivate
nvm:export NVM_DIR="$HOME/.nvm" [ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"Add
nvmto your shell profile so it loads automatically on every login:echo 'export NVM_DIR="$HOME/.nvm"' >> ~/.bashrc echo '[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"' >> ~/.bashrcInstall Node.js (LTS version):
nvm install --lts
Step 3.2: Create and Configure the Server
Create a project directory on your VPS and navigate into it:
mkdir capacities-mcp-server cd capacities-mcp-serverInitialize a Node.js project: This creates the
package.jsonfile.npm init -ySet the project type to "module": Open the
package.jsonwithnano package.jsonand add"type": "module",after the"main": "index.js",line.Install
pm2and the server package locally: We install them here to keep the project self-contained.npm install pm2 @ivotoby/openapi-mcp-server
Step 3.3: Create the Server Configuration
Create an
ecosystem.config.cjsfile forpm2. The.cjsextension is important.nano ecosystem.config.cjsPaste the following configuration into the file. This uses the locally installed
pm2and server script.module.exports = { apps : [{ name : 'capacities-mcp', script : './node_modules/@ivotoby/openapi-mcp-server/dist/cli.js', args : [ '--openapi-spec', 'https://gist.githubusercontent.com/natkitten/37e88b5dab4195b0f4d650f31f5505bf/raw/capacities_openapi_3.json', '--api-base-url', 'https://api.capacities.io', '--headers', 'Authorization:Bearer YOUR_CAPACITIES_API_TOKEN', '--toolNameFormat', '**', '--transport', 'http', '--host', '0.0.0.0', '--port', '8448' // Or your preferred port ] }] }Replace
YOUR_CAPACITIES_API_TOKENwith your actual token.Save and exit (
CTRL + X,Y,Enter).
Step 3.4: Run the Server
Start the server using the local
pm2:./node_modules/pm2/bin/pm2 start ecosystem.config.cjsCheck logs to confirm it's listening on your port:
pm2 logs capacities-mcpSave the configuration for reboots:
pm2 saveEnable
pm2on startup: Runpm2 startupand follow the on-screen instructions.
Step 3.5: Configure Firewall, Caddy, and Genspark
Firewall: Open your chosen port (
8448in this example) on both your VPS firewall (sudo ufw allow 8448) and your cloud provider's firewall (in the Hostinger dashboard).Caddy: For a secure HTTPS URL, set up a reverse proxy in your
Caddyfile.mcp.yourdomain.com { reverse_proxy localhost:8448 }Reload Caddy to apply the changes (
sudo systemctl reload caddy).Genspark:
Server Type:
StreamableHttpServer URL:
https://mcp.yourdomain.com/mcp(using the/mcppath).Request Header:
{"Content-Type": "application/json"}
Add the server and test it.
Licensed under the MIT License — see LICENSE for details
Available Tools
5 toolsget_space_infoC
Get structures and collections of a space
| Name | Required | Description | Default |
|---|---|---|---|
| searchParams | No |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must disclose behavioral traits. It only says 'Get', implying a read operation, but does not elaborate on whether any side effects exist, required permissions, error behavior, or what 'structures and collections' entail. This is insufficient for a tool with no annotation support.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, clean sentence that is front-loaded with the key action. It avoids unnecessary words and is easy to parse. While more detail could be added, the conciseness is appropriate for the limited content it provides.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's simplicity (one parameter, no output schema, no annotations), the description gives a basic idea that the tool returns structures and collections. However, it lacks details on the exact return format, any pagination, error conditions, or what 'structures' and 'collections' mean in this context. It is barely adequate for a minimal understanding.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema has zero description coverage, and the description does not compensate by explaining the spaceid parameter. It only says 'of a space', which weakly hints at the need for a space identifier but does not clarify the parameter format, nesting, or purpose. The parameter name 'spaceid' partially helps, but the description adds minimal value beyond the schema.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description 'Get structures and collections of a space' clearly states a specific verb (Get) and resource (structures and collections of a space), making it evident what the tool does. It does not explicitly differentiate from sibling tools like get_spaces, but the phrase 'of a space' implies it targets a single space's details rather than listing spaces.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no guidance on when to use this tool versus alternatives such as get_spaces or search_content. The description does not state any prerequisites, exclusions, or context in which this tool should be preferred, leaving the agent without explicit selection criteria.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_spacesA
Get your spaces
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must fully disclose behavior. It only states 'Get your spaces' with no mention of authentication, rate limits, pagination, or return format. The verb 'get' implies read-only, but no additional behavioral context is given, making this a minimal disclosure.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single four-word phrase with no wasted language. It is front-loaded and appropriately sized for a tool with no parameters, though it lacks any supplemental details.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a parameterless list tool, the description provides the essential meaning: retrieving spaces. However, it omits any context about the structure of returned data or how it relates to get_space_info, leaving some ambiguity for a complex domain.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
This tool has zero parameters, so the input schema fully covers the parameter space. The description adds nothing about parameters, but none are needed, so the baseline of 4 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description uses the specific verb 'get' and resource 'spaces', clearly indicating a retrieval operation. However, it does not distinguish from sibling tool 'get_space_info', which likely focuses on a single space's details, so it doesn't earn a 5.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description implies usage for retrieving the user's spaces but provides no explicit guidance on when to use this instead of get_space_info or other siblings. There are no stated alternatives or exclusions, so it stays at an implied level.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
save_to_daily_noteC
Save text to today's daily note
| Name | Required | Description | Default |
|---|---|---|---|
| requestBody | No |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description must fully disclose behavioral traits. It only states the basic action and does not explain whether content is appended or overwritten, what permissions are required, or any side effects. This is a significant gap for a mutation tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single concise sentence with no filler, which is structurally efficient. However, it is under-specified, missing essential details about parameters and behavior, so the brevity is not a virtue in this context.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's moderate complexity (nested requestBody, no output schema, no annotations), the description is far from complete. It does not mention that spaceId and mdText are required, nor describe what the tool returns, making it inadequate for safe invocation.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema has one nested requestBody with fields like spaceId and mdText, but the description does not explain any of them. With 0% schema description coverage, the description completely fails to compensate, leaving parameter meanings ambiguous.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description 'Save text to today's daily note' clearly identifies the action (save text) and the resource (today's daily note), which distinguishes it from sibling tools like save_weblink (saving URLs) and search_content. However, it lacks elaboration on what 'text' means or the note's context, but the core purpose is unambiguous.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives such as save_weblink or search_content. There is no mention of prerequisites, preferred use cases, or exclusions, leaving the agent without direction on selection.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
save_weblinkC
Save a weblink to a space
| Name | Required | Description | Default |
|---|---|---|---|
| requestBody | No |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must carry the full burden of behavioral disclosure. It only says 'save a weblink to a space', implying a mutation but providing no details about required permissions, side effects, errors, response behavior, or what happens to existing data. This is insufficient for a write operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single concise sentence with no wasteful words, and it is front-loaded with the verb. However, it is so brief that it lacks structure or elaboration, making it more under-specified than appropriately structured.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the nested requestBody with six properties, no annotations, and no output schema, the description is far too minimal. It provides no information about required fields (e.g., spaceId, url), optional enhancements (tags, mdText), or what the response looks like, leaving the agent without enough context to invoke the tool correctly.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, and the description does not name any parameters. It vaguely maps 'weblink' to the url field and 'space' to spaceId, but completely ignores tags, mdText, titleOverwrite, descriptionOverwrite, and the nested requestBody structure. An agent would have to guess at the meaning of these fields from the schema alone.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description uses a specific verb ('save'), resource ('weblink'), and destination ('space'), which makes the core purpose clear. It is distinguishable from sibling tools like 'get_spaces' and 'save_to_daily_note' due to the explicit target, but it does not explicitly name alternatives or edge cases.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no guidance on when to use this tool vs. alternatives like 'save_to_daily_note', no prerequisites, no context about typical scenarios, and no mention of limitations. The description simply states what it does, not when to choose it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
search_contentD
Search for content
| Name | Required | Description | Default |
|---|---|---|---|
| requestBody | No |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations available, the description must disclose behavioral traits, but it only says 'search' without explaining return format, filtering behavior, pagination, limitations, or side effects. The nested schema hints at advanced capabilities, but the description offers no behavioral context beyond the name.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is short, but the single phrase 'Search for content' is under-specified rather than appropriately concise. It does not earn its place because it adds no information beyond the tool name, making it a case of under-specification, not efficiency.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's nested requestBody schema, enum values, required fields, and lack of output schema or annotations, the description is drastically incomplete. It provides no context about how the tool fits into the broader workspace of sibling tools or what an agent should expect when invoking it.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema description coverage is 0%, so the description must compensate by explaining the requestBody fields (searchTerm, spaceIds, mode, filterStructureIds). It provides no such explanation, leaving the agent to infer parameter semantics solely from schema structure, which is insufficient for correct invocation.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description 'Search for content' essentially restates the tool name without adding specificity about what content is searched, in what scope, or how it differs from sibling tools like get_spaces or get_space_info. It is a tautological expression of the name, not a meaningful clarification of purpose.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance is provided on when to use this tool versus alternatives such as get_spaces or get_space_info. The description does not mention intended use cases, prerequisites, or conditions under which search_content is preferred. There is no misleading information, but also no direction.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
5 tool updates
v1.0.0- First observed
get_space_info - First observed
get_spaces - First observed
save_to_daily_note - First observed
save_weblink - First observed
search_content
TDQS
Scored across 5 tools
Each tool targets a distinct action and resource: list spaces, get space details, save text to daily note, save weblink, and search. There is no overlap or ambiguity between tool purposes.
All tool names follow a consistent verb_noun pattern with lowercase and underscores (e.g., get_spaces, save_to_daily_note, search_content). The naming style is uniform and predictable.
5 tools is well-scoped for a lightweight bridge. It provides core read, write, and search capabilities without unnecessary redundancy or bloat.
The toolset covers essential workflows: retrieving spaces, saving content, and searching. Minor gaps exist such as lack of general note creation or update/delete operations, but these are acceptable for an unofficial bridge.
Maintenance
Related MCP Connectors
MCP-native notes and memory for ChatGPT, Claude, and other AI tools.
- TaprootOAuthcom.taproothq
Persistent memory layer for AI tools. Save and recall notes across Claude and other MCP clients.
Connect AI to your flomo notes. Search, create, edit notes and manage tags via MCP.
Search, read, and write your Apple Notes from ChatGPT/Claude via a local Mac agent + MCP relay.
Related MCP Servers
- AlicenseAqualityCmaintenanceAn enhanced MCP server for the Capacities knowledge management app. Features * List and explore spaces * Search content with full-text and title modes * Read full object content by ID (unique feature) * Save weblinks with tags and metadata * Add content to daily notes * Windows-compatible6132MIT
- FlicenseNot gradedqualityDmaintenanceEnables to manage notes and collections in Fastidious AI application through natural language, supporting CRUD operations and search via MCP protocol.-
- FlicenseNot gradedqualityDmaintenanceEnables interaction with Notion workspaces, allowing users to search, query databases, create/update pages, and manage content via natural language through MCP.-
- AlicenseNot gradedqualityAmaintenanceEnables search, content creation, weblink saving, and knowledge base analysis with Capacities through any MCP-compatible client.7MIT