Add a new ReVision tool

The four tools (Analyzer, Enhance, Translate, Jargonary) all live in src/revision/static/index.html. Adding a tool is almost entirely a frontend change — the backend /api/messages proxy is generic and usually needs no edits.

Anatomy of a tool

Each tool is a tab wired through three parts of index.html:

1. Tab button — in the tab bar (~line 481):

   <button class="tab-btn" data-tab="mytool">🛠️ My Tool</button>
   

2. Tab panel — a matching content section (~line 488+):

   <div id="mytool" class="tab-content">
       <textarea id="mytoolInput" placeholder="..."></textarea>
       <button id="mytoolBtn">Run</button>
       <div id="mytoolResults"></div>
   </div>
   

   The tab switcher (~line 714) toggles .active by matching data-tab to the panel id, so the button's data-tab must equal the panel's id.
3. Behavior — a click handler that builds a prompt and calls the shared helper callClaude(prompt, maxTokens = 3000) (~line 727), which POSTs to /api/messages and returns the model's text (reads data.error.message on failure).

Steps

1. Add the tab button (step 1) and panel (step 2), keeping ids consistent.
2. Add a handler modeled on an existing one (e.g. the Enhance handler, ~line 900): read inputs, build the prompt, await callClaude(...), render into the results div. Escape untrusted model/user text with escapeHtml before injecting into HTML; use storeForClipboard + copyStored for copy buttons, following existing tools.
3. If the tool needs structured output, prompt for JSON only and strip code fences before JSON.parse, as the Analyzer does (~line 837).

Guardrails

• Do not call api.anthropic.com from the browser or embed the key — always go through same-origin /api/messages. The key and model stay server-side.
• Only change the backend if the tool needs a genuinely new capability (e.g. a new endpoint). If you do, add a test in tests/test_server.py using the injected-client seam, and keep the backend stdlib-only.
• Update the tool list in README.md and CLAUDE.md (project overview) so docs don't drift.

After changes, verify with the run-app skill and run the test-and-lint skill.