Prism.nvim - Claude Code + Neovim Integration

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Handle Arguments

Based on $ARGUMENTS:

•install (or no args): Run full installation (idempotent)
•update: Update prism to latest version
•status: Check installation status and MCP connection
•help: Show usage information and available commands

Command: help

Display this information:

code

/prism - Neovim integration with Claude Code

Commands:
  /prism install  - Install or reinstall prism.nvim (idempotent)
  /prism update   - Update to latest version
  /prism status   - Check installation and MCP connection
  /prism help     - Show this help

After install:
  1. Restart Claude Code to load MCP server
  2. Open Neovim, press Ctrl+; to toggle Claude terminal
  3. Talk naturally: "go to line 42", "fix this error", "commit with message X"

Shell commands (after install):
  nvc              - Open nvim with Claude
  nvc -c           - Continue last conversation
  nvc --model opus - Use Opus model
  nvco             - Shortcut for nvc --model opus

Command: update

Quick update without full reinstall:

bash

PRISM_DIR="$HOME/.local/share/prism.nvim"
if [ ! -d "$PRISM_DIR" ]; then
  echo "Prism not installed. Run /prism install first."
  exit 1
fi

cd "$PRISM_DIR"
OLD_VERSION=$(grep '^version' pyproject.toml 2>/dev/null | cut -d'"' -f2)
echo "Current version: $OLD_VERSION"

git fetch origin main --quiet
BEHIND=$(git rev-list HEAD..origin/main --count 2>/dev/null || echo "0")

if [ "$BEHIND" -eq 0 ]; then
  echo "Already up to date"
else
  echo "Updating ($BEHIND commits behind)..."
  git pull
  NEW_VERSION=$(grep '^version' pyproject.toml | cut -d'"' -f2)
  echo "Updated to version: $NEW_VERSION"

  if [ "$OLD_VERSION" != "$NEW_VERSION" ]; then
    echo ""
    echo "Version changed: $OLD_VERSION -> $NEW_VERSION"
    echo "Restart Claude Code to apply changes."
  fi
fi

After git pull, check if shell functions need updating:

bash

PRISM_DIR="$HOME/.local/share/prism.nvim"
REF_BASH="$PRISM_DIR/scripts/shell/nvc.bash"

for rc in ~/.zshrc ~/.bashrc; do
  if [ -f "$rc" ] && grep -q "nvc()" "$rc"; then
    installed=$(sed -n '/^# Prism.nvim helpers/,/^alias nvco=/p' "$rc")
    ref_content=$(cat "$REF_BASH")
    if [ "$installed" != "$ref_content" ]; then
      echo "shell_$(basename $rc):outdated"
    fi
  fi
done

If any shell functions are outdated, use AskUserQuestion:

code

question: "Your nvc shell function is outdated. Update to latest version?"
header: "Update nvc"
options:
  - label: "Yes, update (Recommended)"
    description: "Replace old nvc function with latest version"
  - label: "No, keep current"
    description: "Keep your existing function"

If user says yes, update the function:

bash

sed -i.bak '/^# Prism.nvim helpers/,/^alias nvco=/d' ~/.bashrc  # or ~/.zshrc
cat "$PRISM_DIR/scripts/shell/nvc.bash" >> ~/.bashrc  # or ~/.zshrc
echo "Shell function updated. Run: source ~/.bashrc"

After running, tell the user:

•If version changed: Restart Claude Code to load updated MCP server
•If shell updated: Source your rc file or restart terminal
•Check the changelog for new features

Command: status

Run these checks and report results in a table:

bash

PRISM_DIR="$HOME/.local/share/prism.nvim"
if [ -d "$PRISM_DIR" ]; then
  cd "$PRISM_DIR"
  LOCAL_VERSION=$(grep '^version' pyproject.toml 2>/dev/null | cut -d'"' -f2)
  git fetch origin main --quiet 2>/dev/null
  BEHIND=$(git rev-list HEAD..origin/main --count 2>/dev/null || echo "?")
  echo "version:$LOCAL_VERSION"
  echo "behind:$BEHIND"
else
  echo "version:not installed"
fi

bash

python3 -c "import msgpack" 2>/dev/null && echo "msgpack:ok" || echo "msgpack:missing"
[ -L ~/.local/share/nvim/site/pack/prism/start/prism.nvim ] && echo "plugin:linked" || echo "plugin:missing"
grep -q '"prism-nvim"' ~/.claude/settings.json 2>/dev/null && echo "mcp:configured" || echo "mcp:missing"
[ -L ~/.claude/rules/prism-nvim.md ] && echo "rules:linked" || echo "rules:missing"
[ -f ~/.config/nvim/lua/plugins/prism.lua ] && echo "nvim_config:exists" || echo "nvim_config:missing"

bash

# Check shell aliases by comparing content directly (portable, works on macOS/Linux)
PRISM_DIR="$HOME/.local/share/prism.nvim"
REF_BASH="$PRISM_DIR/scripts/shell/nvc.bash"

check_shell_func() {
  local rc="$1"
  local name="$2"
  if [ ! -f "$rc" ]; then return; fi
  if ! grep -q "nvc()" "$rc" 2>/dev/null; then return; fi

  # Extract nvc function block from rc file
  local installed=$(sed -n '/^# Prism.nvim helpers/,/^alias nvco=/p' "$rc" 2>/dev/null)
  if [ -z "$installed" ]; then
    # Try alternate extraction - just the function
    installed=$(sed -n '/^nvc()/,/^}/p' "$rc" 2>/dev/null)
  fi

  if [ -n "$installed" ]; then
    # Compare content directly instead of using hashes
    local ref_content=$(cat "$REF_BASH")
    if [ "$installed" = "$ref_content" ]; then
      echo "shell_$name:current"
    else
      echo "shell_$name:outdated"
    fi
  else
    echo "shell_$name:configured"
  fi
}

check_shell_func ~/.zshrc zsh
check_shell_func ~/.bashrc bash
grep -q "nvc()" ~/.zshrc ~/.bashrc 2>/dev/null || echo "shell:missing"

Also try MCP connection: mcp__prism-nvim__get_current_file

•If it works: MCP connected
•If it fails: MCP not connected (Neovim may not be running)

Present results as:

Component	Status
Version	X.Y.Z (N commits behind)
Python msgpack	OK / Missing
Neovim plugin	Linked / Missing
MCP server	Configured / Missing
Rules	Linked / Missing
Nvim config	Exists / Missing
Shell alias	Current / Outdated / Missing
MCP connection	Connected / Not connected

If any component is missing, suggest running /prism install. If shell alias shows "Outdated", suggest running /prism install to update the nvc function.

Command: install

Full installation (all steps are idempotent - safe to run multiple times).

Step 1: Clone or Update Repository

bash

PRISM_DIR="$HOME/.local/share/prism.nvim"
if [ -d "$PRISM_DIR" ]; then
  cd "$PRISM_DIR"
  LOCAL_VERSION=$(grep '^version' pyproject.toml 2>/dev/null | cut -d'"' -f2)
  echo "Current version: $LOCAL_VERSION"

  git fetch origin main --quiet
  BEHIND=$(git rev-list HEAD..origin/main --count 2>/dev/null || echo "0")

  if [ "$BEHIND" -gt 0 ]; then
    echo "Updates available ($BEHIND commits behind)"
    git pull
    NEW_VERSION=$(grep '^version' pyproject.toml | cut -d'"' -f2)
    echo "Updated to version: $NEW_VERSION"
  else
    echo "Already up to date"
  fi
else
  git clone https://github.com/genomewalker/prism.nvim.git "$PRISM_DIR"
  cd "$PRISM_DIR"
  VERSION=$(grep '^version' pyproject.toml | cut -d'"' -f2)
  echo "Installed version: $VERSION"
fi

Step 2: Install Python Dependencies

bash

python3 -c "import msgpack" 2>/dev/null && echo "msgpack already installed" || python3 -m pip install --user msgpack

Step 3: Link Neovim Plugin

bash

PACK_DIR="$HOME/.local/share/nvim/site/pack/prism/start"
if [ -L "$PACK_DIR/prism.nvim" ]; then
  echo "Neovim plugin already linked"
else
  mkdir -p "$PACK_DIR"
  ln -sf "$HOME/.local/share/prism.nvim" "$PACK_DIR/prism.nvim"
  echo "Neovim plugin linked"
fi

Step 4: Register MCP Server

First check if prism-nvim already exists in ~/.claude/settings.json:

bash

grep -q '"prism-nvim"' ~/.claude/settings.json && echo "MCP already configured"

Only if not configured, use Edit tool to add to mcpServers:

json

"prism-nvim": {
  "type": "stdio",
  "command": "python3",
  "args": ["-m", "prism_nvim.mcp_server"],
  "cwd": "~/.local/share/prism.nvim"
}

Step 5: Create Neovim Config

Check if exists first: ~/.config/nvim/lua/plugins/prism.lua

If file exists, skip. Otherwise create:

lua

-- Prism.nvim - Claude Code Integration
return {
  {
    dir = vim.fn.expand("~/.local/share/prism.nvim"),
    name = "prism.nvim",
    lazy = false,
    dependencies = {
      "MunifTanjim/nui.nvim",
    },
    config = function()
      require("prism").setup({
        mcp = { auto_start = false },
        terminal = {
          provider = "native",
          position = "vertical",
          width = 0.4,
          auto_start = false,
          passthrough = true,
        },
        claude = { model = nil, continue_session = false },
        trust = { mode = "companion" },
      })
    end,
    keys = {
      { "<leader>cc", "<cmd>Prism<cr>", desc = "Prism: Open Layout" },
      { "<leader>ct", "<cmd>PrismToggle<cr>", desc = "Prism: Toggle Terminal" },
      { "<leader>cs", "<cmd>PrismSend<cr>", mode = { "n", "v" }, desc = "Prism: Send to Claude" },
      { "<leader>ca", "<cmd>PrismAction<cr>", mode = { "n", "v" }, desc = "Prism: Code Actions" },
      { "<C-\\>", "<cmd>PrismToggle<cr>", desc = "Toggle Prism Terminal" },
    },
  },
}

Step 6: Link Claude Instructions

Check first:

bash

[ -L ~/.claude/rules/prism-nvim.md ] && echo "Rules already linked"

Only if not linked:

bash

mkdir -p ~/.claude/rules
ln -sf ~/.local/share/prism.nvim/CLAUDE.md ~/.claude/rules/prism-nvim.md
echo "Rules linked"

Step 7: Add or Update Shell Aliases

First, check existing shell functions and compare with reference:

bash

PRISM_DIR="$HOME/.local/share/prism.nvim"
REF_BASH="$PRISM_DIR/scripts/shell/nvc.bash"
REF_FISH="$PRISM_DIR/scripts/shell/nvc.fish"

# Check each shell rc file
for rc in ~/.zshrc ~/.bashrc; do
  if [ -f "$rc" ] && grep -q "nvc()" "$rc"; then
    # Extract installed function
    installed=$(sed -n '/^# Prism.nvim helpers/,/^alias nvco=/p' "$rc")
    ref_content=$(cat "$REF_BASH")

    if [ "$installed" != "$ref_content" ]; then
      echo "shell_$(basename $rc):outdated"
    else
      echo "shell_$(basename $rc):current"
    fi
  else
    echo "shell_$(basename $rc):missing"
  fi
done

If missing: Use AskUserQuestion to ask which shell:

code

question: "Which shell do you use?"
header: "Shell"
options:
  - label: "Zsh"
    description: "Add aliases to ~/.zshrc"
  - label: "Bash"
    description: "Add aliases to ~/.bashrc"
  - label: "Fish"
    description: "Add functions to ~/.config/fish/functions/"
  - label: "Skip"
    description: "Don't add shell aliases"

If outdated: Use AskUserQuestion to offer update:

code

question: "Your nvc shell function is outdated. Update to latest version?"
header: "Update"
options:
  - label: "Yes, update it (Recommended)"
    description: "Replace old nvc function with latest version"
  - label: "No, keep current"
    description: "Keep your existing function (may miss bug fixes)"

To update outdated function: Remove old block and append new:

bash

# Remove old prism block from rc file
sed -i.bak '/^# Prism.nvim helpers/,/^alias nvco=/d' ~/.bashrc  # or ~/.zshrc

# Append new version
cat "$PRISM_DIR/scripts/shell/nvc.bash" >> ~/.bashrc  # or ~/.zshrc

For new installs, append the reference file:

bash

# For Bash/Zsh - append the reference file
cat "$PRISM_DIR/scripts/shell/nvc.bash" >> ~/.bashrc  # or ~/.zshrc

For Fish (~/.config/fish/functions/nvc.fish and nvco.fish):

bash

# Copy reference files for Fish
mkdir -p ~/.config/fish/functions
cp "$PRISM_DIR/scripts/shell/nvc.fish" ~/.config/fish/functions/nvc.fish
cp "$PRISM_DIR/scripts/shell/nvco.fish" ~/.config/fish/functions/nvco.fish

After Installation

Tell the user:

•Restart Claude Code to load the MCP server
•Open Neovim - prism loads automatically
•Press Ctrl+; to toggle Claude terminal
•*Use Ctrl+\ Ctrl+* to exit terminal mode (passthrough)

Token Savings

Explain that MCP tools save tokens because:

•Vim commands are ~20 tokens (e.g., %s/old/new/g)
•Standard Edit tool sends full file content (~500-2000 tokens)
•For a 500-line file, that's 25-100x savings per edit

Natural Language Interface

Prism's 55+ MCP tools respond to natural language:

You say	Claude does
"go to line 42"	`goto_line(42)`
"show me errors"	`get_diagnostics`
"fix this error"	`fix_diagnostic`
"replace foo with bar"	`search_and_replace("foo", "bar")`
"be more careful"	`set_trust_mode("guardian")`
"just do it"	`set_trust_mode("autopilot")`
"teach me vim"	`set_config(narrated=true)`
"commit with message X"	`git_commit("X")`
"who wrote this?"	`git_blame`

See CLAUDE.md for the complete natural language reference.