Problem

The MCPB bundle (gitlab-mcp-6.41.1.mcpb) is 84 MB compressed / 281 MB uncompressed with 13,433 files.

Root Causes

1. prisma in dependencies — The Prisma CLI is only needed for prisma generate during build, not at runtime. Being in dependencies means npm install --production installs it and ALL its transitive deps (typescript, @electric-sql, effect, chevrotain, etc.)

2. @prisma/client declares prisma as peerDependency — npm 7+ auto-installs peer deps even with --production, pulling in the CLI again.

3. Unused packages in dependencies — form-data (never imported, Node.js has native FormData), @graphql-typed-document-node/core (type-only imports, erased at compile time).

4. build-mcpb.sh doesn't clean up enough — Only removes *.md, LICENSE*, __tests__/ but leaves source maps, .d.ts, fixture directories.

Solution

Step 1: Move build-only packages to devDependencies

• prisma — only needed for prisma generate during build
• @graphql-typed-document-node/core — type-only imports (erased at compile time)

Step 2: Remove unused packages

• form-data — never imported in src/, Node.js 24 has native FormData

Step 3: Use --omit=peer in npm install

Prevents npm from auto-installing prisma CLI and typescript as @prisma/client peer dependencies.

Step 4: Enhanced cleanup in build-mcpb.sh

• Remove source maps (*.js.map) from node_modules and dist/
• Remove TypeScript declarations (*.d.ts, *.d.mts) from node_modules
• Remove fixture/example/doc directories
• Remove package-lock.json, tsconfig.build.tsbuildinfo

Result

Files Modified