[FEATURE] Claude Desktop: Allow permanent auto-approval of read-only MCP tools (Read, Grep, Glob, WebSearch, WebFetch)

Problem

When Claude Code runs as an MCP server inside Claude for Desktop, every MCP tool call requires manual permission approval — including completely read-only, zero-risk tools like Read, Grep, Glob, WebSearch, and WebFetch.

This creates enormous friction. A single research task can trigger dozens of permission prompts for tools that literally cannot modify anything.

Meanwhile, in the Claude Code CLI, these same tools are already auto-allowed by default — they never prompt for permission, because Anthropic correctly identified them as non-destructive. This inconsistency between the CLI and MCP-in-Desktop experiences is the core issue.

Current behavior

1. User configures Claude Code as an MCP server in Claude Desktop
2. User asks Claude to research something / explore a codebase
3. Claude attempts to call Read, Grep, Glob, WebSearch, or WebFetch
4. Claude Desktop prompts: "Allow this tool call?"
5. User clicks "Allow" (or "Allow for this chat" if available)
6. Steps 3-5 repeat dozens of times per conversation
7. There is no "always allow" option that persists across chats

Desired behavior

Allow users to permanently auto-approve specific MCP tools — either through:

• A global setting in Claude Desktop preferences (e.g., per-tool or per-tool-category allowlist)
• Respecting the permission tiers already built into Claude Code (read-only = auto-allowed)
• A per-MCP-server trust configuration (e.g., "trust all read-only tools from this server")
• Or at minimum, a blanket "read-only MCP tools are always allowed" toggle

Why this matters

• Read-only tools cannot cause harm — they don't write files, don't execute commands, don't send data anywhere
• Claude Code CLI already auto-allows them — the risk assessment has already been done
• The current UX makes Claude Desktop + Claude Code MCP nearly unusable for research-heavy or exploration-heavy workflows
• This is the #1 friction point in the Claude Desktop + MCP experience for power users

Related issues

• #7328 — MCP Tool Filtering (focused on context window, but overlapping concern)
• #10801 — No way to bypass MCP tool approval prompts in VSCode extension

Environment

• Claude for Desktop (macOS)
• Claude Code running as MCP server
• Affected tools: Read, Grep, Glob, WebSearch, WebFetch, and other non-destructive MCP tools