This server provides two clearly-named installation tools with reasonable schemas and descriptions. However, there are notable gaps in parameter descriptions, missing output schema documentation, and no structured error handling guidance. Tool names follow verb_noun convention well (install_repo_*, install_local_*), descriptions are present and adequate (80-120 chars), and input schemas use Zod with basic type definitions. The main weaknesses are: (1) parameter descriptions for 'args' and 'env' are minimal and don't explain format constraints ('delimited by =' is mentioned but not actionable for LLMs); (2) no documented output schema structure, the code returns {content, isError} but this is not declared anywhere visible to the agent; (3) error handling is basic, many failure modes (missing config file, invalid paths, spawn failures) return generic error messages without recovery guidance; (4) no batch operations or pagination support (not critical for this use case, but relevant for composition). The schema score is capped at 50-60 because while Zod schemas are present, they lack sufficient constraint documentation (e.g., what are valid values for 'args'? What format for 'env'?). Overall, this is a solid community tool with functional definitions but missing some production-grade polish around LLM ergonomics.

• Add explicit output schema documentation: 'Returns {content: [{type: "text", text: string}], isError: boolean}. On success, isError is false and text contains the server config confirmation. On failure, isError is true and text explains what went wrong.'
• Improve 'env' parameter description: 'Environment variables as KEY=VALUE pairs (e.g., ["PYTHONPATH=/usr/lib", "DEBUG=true"]). Each item must contain exactly one equals sign.'
• Improve 'args' parameter description: 'Command-line arguments to pass to the MCP server (e.g., ["--port", "8000", "--verbose"]). Provide as array of individual argument strings, not space-separated.'
• Add to both tool descriptions: 'This is a WRITE operation that modifies your client configuration files. The installation is permanent until manually reverted.'
• Enhance error messages with recovery paths. Example: 'npm package "pkg-name" not found. Verify the package name via npm search, or use install_local_mcp_server to install from a local path instead.'
• Classify errors explicitly in error responses. For network timeouts: 'Unable to verify npm package (network error). This is retryable.' For invalid names: 'Invalid package name. Package names must be lowercase alphanumeric with hyphens.'
• Clarify 'host' parameter: 'Target application where the MCP server will be registered (claude, claude-code, cursor, vscode). If omitted, auto-detects based on which apps are installed (checks in order: cursor, vscode, claude-code, claude).'
• Add Zod constraint decorations for enums to improve schema introspection: already using .enum() which is correct; ensure all enum types are as tight as possible.