Reuse existing URLs, commands, headers, env references, and cwd.
Heavy MCP tools don’t belong in your prompt.
ToolCapsule inventories existing MCPs, turns selected heavy servers into lazy-loaded, file-first Agent Skills, and keeps calls patchable and retryable.
npx skills add RainSunMe/toolcapsule --skill toolcapsule
Then ask your agent to run tcap init --url .
Copy a detailed prompt for Claude Code, GitHub Copilot / VS Code, OpenCode, Gemini CLI, or Cursor so it can import your MCP setup safely.
The problem
MCP made tools universal. It also made tool context heavier.
Native MCP is excellent for small, frequent tools. But document and workflow MCP servers often expose long descriptions, schemas, and rules that can be visible to the model even when the user is only planning.
ToolCapsule keeps MCP as the capability layer and uses Skills as the agent-facing workflow layer. Full schemas are still available, but no longer need to be carried every turn.
MCP-to-Skill conversion
Turn existing MCP config into a lazy-loaded Agent Skill.
ToolCapsule reads MCP registrations you already have and writes a profile plus an Agent Skill for Claude Code, GitHub Copilot / VS Code, OpenCode, Gemini CLI, or Cursor.
$ tcap init --url
STATUS NAME SCOPE SOURCE MODE PATH
● on github workspace vscode native .vscode/mcp.json
● on notion workspace claude native .mcp.json
$ tcap init github --target claude
created ~/.toolcapsule/profiles/github.json
created .claude/skills/github-mcp/SKILL.md
$ tcap tools github --brief
Workspace config first; user-level config requires opt-in.
Default target is Claude, with Copilot, OpenCode, .agents, or all targets available.
The capsule
A tool call becomes a patchable artifact.
Instead of asking the model to regenerate a large tool call after a failure, ToolCapsule stores the arguments, payloads, request, response, and error as local files.
args.json
content.md
request.json
response.json
error.txt
command.txt
Discover briefly
List MCP tools as compact summaries instead of injecting every schema.
Write locally
Put Markdown, JSON, and long arguments into files the agent can patch.
Call deterministically
Run the MCP tool through a CLI and save the full request/response trace.
Patch and retry
Fix the local file and replay the same tool call without rewriting the prompt.
Native MCP
Regenerate the call
- Tool schemas stay close to the prompt.
- Large payloads are reassembled by the model.
- Retries can accidentally change correct content.
ToolCapsule
Patch the artifact
- Schemas are lazy-loaded when needed.
- Payloads live in
args.jsonand content files. - Retries are auditable, local, and deterministic.
For heavy MCP servers
Keep the protocol. Change the workflow.
ToolCapsule is designed for Feishu/Lark, Notion, Jira, Linear, Confluence, GitHub management tools, and internal SaaS MCPs.
Start with ToolCapsule