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CHANGE_ME
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nvm, mcp tool search, tmux, etc
what a day! so many things that I learned.
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‎journals/2026_03_16.md‎

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- # [[Filed]]
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- [[nvf]]
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- [[Person/raf]]
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- [[MCP/Tool Search]]
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- [[nvim/Q/How can I quickly collapse and expand a block in nvim?]]
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- [[nvim-ufo]]

‎pages/Claude Code___Q___In what sense are MCP tools loaded on-demand.md‎

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- # In what sense are [[MCP]] tools "loaded on-demand" in [[Claude Code]]?
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- ## Answer
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- [[AI/Response]]
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- "Loaded on-demand" refers to a specific [[Claude Code]] feature called **MCP Tool Search**. [Official docs: Scale with MCP Tool Search](https://code.claude.com/docs/en/mcp#scale-with-mcp-tool-search)
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- **How it works** (from official docs):
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- Claude Code automatically enables Tool Search when MCP tool descriptions would consume more than **10% of the context window**
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- When triggered: MCP tools are **deferred** rather than loaded into context upfront
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- Claude uses a built-in search tool (`MCPSearch`) to discover relevant MCP tools when it needs them
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- Only the tools Claude actually needs are then loaded into context
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- **Why?** Tool definitions from many MCP servers can be verbose and numerous — loading them all upfront could consume a significant slice of the context window even when most are never used in a session.
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- **Default behaviour**: Enabled by default (except when `ANTHROPIC_BASE_URL` points to a non-first-party host, since most proxies don't forward `tool_reference` blocks). Requires Sonnet 4+ or Opus 4+; Haiku models don't support it.
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- **Control via env var** `ENABLE_TOOL_SEARCH`:
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- `(unset)` — enabled by default
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- `auto` — activates when MCP tools exceed 10% of context
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- `auto:<N>` — custom threshold (e.g. `auto:5` for 5%)
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- `true` — always on, including non-first-party base URLs
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- `false` — disabled; all MCP tools loaded upfront
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- You can also disable the search tool specifically: `permissions.deny: ["MCPSearch"]`
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- ## Related
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- [[MCP]]
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- [[Claude Code]]

‎pages/MCP___Tool Search.md‎

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tags:: [[MCP]], [[AI/Coding]], [[Claude Code]], [[OpenAI]]
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- # MCP Tool Search
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- Both [[Anthropic]] ([[Claude Code]]) and [[OpenAI]] have independently shipped a mechanism for loading [[MCP]] tool definitions **on-demand** rather than injecting all of them into the context window upfront — directly addressing the context bloat problem described in [[MCP/Concept/On-Demand Tool Loading]].
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- ## The Problem
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- Geoffrey Huntley's [too many model context protocol servers and LLM allocations on the dance floor](https://simonwillison.net/2025/Aug/22/too-many-mcps/) (via [[Person/Simon Willison]]) crystallised the issue:
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- Claude's 200k-token window shrinks to ~176k after system prompts in tools like Amp or Cursor
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- The GitHub MCP server alone consumes ~55,000 of those tokens
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- Multiple MCP servers stack this penalty; LLMs also perform worse when irrelevant information fills the prompt
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- ## Anthropic's Solution: MCP Tool Search (Claude Code)
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- [Scale with MCP Tool Search - Claude Docs](https://code.claude.com/docs/en/mcp#scale-with-mcp-tool-search)
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- Enabled by default in [[Claude Code]] when MCP tool schemas would exceed **10% of the context window**
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- When triggered:
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- MCP tools are **deferred** — not loaded into context upfront
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- Claude uses a built-in `MCPSearch` tool to discover relevant tools when it needs them
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- Only the tools actually needed are loaded into context for that turn
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- Controlled via `ENABLE_TOOL_SEARCH` env var; requires Sonnet 4+ or Opus 4+
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- See also: [[Claude Code/Q/In what sense are MCP tools loaded on-demand]]
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- ## OpenAI's Solution: Tool Search (GPT-5.4+)
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- [Tool Search - OpenAI API Docs](https://developers.openai.com/api/docs/guides/tools-tool-search)
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- Introduced with `gpt-5.4`; tools marked `"defer_loading": true` are not injected upfront
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- Two modes:
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- **Hosted**: OpenAI's servers handle discovery automatically; model receives a `tool_search_call` then `tool_search_output`
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- **Client-executed**: The application controls discovery logic and returns matching tools via `tool_search_output`
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- Loaded tools are injected at the **end** of the context window, preserving cache across requests
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- Works with functions, namespaces, or MCP servers
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- ## Significance
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- Both implementations converge on the same architecture: tools as a **searchable index** rather than a flat pre-loaded list
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- This makes large MCP inventories (dozens of servers, hundreds of tools) practical without the context tax
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- Likely to become a baseline expectation for AI coding tools and agent frameworks going forward

‎pages/Person___raf.md‎

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alias:: [[Username/NotAShelf]]
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tags:: [[Coder]]
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- # [raf](https://notashelf.dev)
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- > Political Scientist, Open source advocate, (dys)functional/high-level programmer. @NixOS hacker and nixpkgs contributor.
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- [[Person/raf/GitHub]] https://github.com/NotAShelf
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- [[Person/raf/Blog]] https://notashelf.dev/posts
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- [[Person/raf/TwitX]] https://twitter.com/NotAShelf
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- Maintains [[nvf]] and many other [[NixOS]] and [[Nix]] ecosystem tools
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- ## My Notes
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- Their [[GitHub]] profile is a great example of a well-configured GitHub about page / person README page.

‎pages/nvf.md‎

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- [NotAShelf/nvf: Modular, extensible and distro-agnostic Neovim configuration framework for Nix/NixOS](https://github.com/NotAShelf/nvf)
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alias:: [[Person/raf/GitHub/nvf]]
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logseq-entity:: [[Logseq/Entity/software-project]]
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created-by:: [[Person/raf]]
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- # [nvf](https://github.com/NotAShelf/nvf)
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- A highly modular, extensible, and distro-agnostic [[nvim]] configuration framework for [[Nix]]/[[NixOS]].
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- Documentation: https://nvf.notashelf.dev
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- ## Key Features
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- Declarative [[nvim]] configuration using [[Nix]]
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- Supports standalone, NixOS module, and Home-Manager module installation
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- Prebuilt configs: "Nix" (Nix LSP) and "Maximal" (full LSP + plugins)
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- Portable — test configurations without permanent installation via [[Nix]]

‎pages/tmux___How To___Reload Config.md‎

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‎pages/tmux___Tutorial___26___01___Oboe - Mastering AI Dev Workflows.md‎

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- [[Tip]] Many users find the default [[tmux/Keyshort/Prefix]] prefix key, `Ctrl+b`, a bit awkward. A common alternative is `Ctrl+a`, which is easier to reach
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- [[tmux/How To/Reload Config]]
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- use [[tmux/Keyshort/Prefix]] then `:` then type `source-file ~/.tmux.conf` and press Enter.
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id:: 697d04c1-9250-4237-953e-dd6d4160380c
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