feat(relay): add cost estimation to chat usage and update dashboard

pricing.json

@@ -17,6 +17,12 @@
       "cacheWrite": "cache write price (Anthropic: 1.25x input, OpenAI: ~same as input)"
     }
   },
+  "claude-opus-4-7": {
+    "input": 5,
+    "output": 25,
+    "cacheRead": 0.5,
+    "cacheWrite": 6.25
+  },
   "claude-opus-4-6": {
     "input": 5,
     "output": 25,

relay-server.js

@@ -4,6 +4,22 @@ const path = require('path');
 const os = require('os');
 const fs = require('fs');
 const crypto = require('crypto');
+const { calculateCost } = require('./pricing');
+
+// Estimate USD cost for a single chat's token usage. A chat may list multiple
+// models without a per-model token split, so tokens are divided evenly across
+// the models used. Unpriced models contribute 0 (matches Cost Analysis behavior).
+function estimateChatCost(modelsJson, inputTokens, outputTokens) {
+  let models = [];
+  try { models = JSON.parse(modelsJson || '[]'); } catch {}
+  if (models.length === 0) return 0;
+  const n = models.length;
+  let cost = 0;
+  for (const m of models) {
+    cost += calculateCost(m, (inputTokens || 0) / n, (outputTokens || 0) / n) || 0;
+  }
+  return cost;
+}
 
 const CACHE_DIR = path.join(os.homedir(), '.agentlytics');
 const RELAY_DB_PATH = path.join(CACHE_DIR, 'relay.db');
@@ -164,18 +180,23 @@ function createRelayApp() {
         userEditorMap[r.username][r.source] = r.count;
       }
 
-      const perUserModels = db.prepare(`
-        SELECT rcs.username, rcs.models
+      const perChatStats = db.prepare(`
+        SELECT rcs.username, rcs.models, rcs.total_input_tokens, rcs.total_output_tokens
         FROM relay_chat_stats rcs
       `).all();
       const userModelMap = {};
-      for (const r of perUserModels) {
+      const userCostMap = {};
+      let totalCost = 0;
+      for (const r of perChatStats) {
         if (!userModelMap[r.username]) userModelMap[r.username] = {};
         try {
           for (const m of JSON.parse(r.models || '[]')) {
             userModelMap[r.username][m] = (userModelMap[r.username][m] || 0) + 1;
           }
         } catch {}
+        const cost = estimateChatCost(r.models, r.total_input_tokens, r.total_output_tokens);
+        userCostMap[r.username] = (userCostMap[r.username] || 0) + cost;
+        totalCost += cost;
       }
 
       const totalTokens = db.prepare(`
@@ -199,6 +220,7 @@ function createRelayApp() {
         totalMessages: totalTokens.messages,
         totalInputTokens: totalTokens.inputTokens,
         totalOutputTokens: totalTokens.outputTokens,
+        totalCost,
         editors: editorBreakdown.map(e => ({ source: e.source, count: e.count, users: e.users })),
         topModels: Object.entries(modelFreq).sort((a, b) => b[1] - a[1]).slice(0, 15).map(([name, count]) => ({ name, count })),
         users: perUser.map(u => ({
@@ -210,6 +232,7 @@ function createRelayApp() {
           totalMessages: u.totalMessages,
           totalInputTokens: u.totalInputTokens,
           totalOutputTokens: u.totalOutputTokens,
+          totalCost: userCostMap[u.username] || 0,
           topModels: Object.entries(userModelMap[u.username] || {}).sort((a, b) => b[1] - a[1]).slice(0, 5).map(([name, count]) => ({ name, count })),
           sharedProjects: JSON.parse((users.find(x => x.username === u.username) || {}).projects || '[]'),
         })),

ui/src/pages/RelayDashboard.jsx

@@ -8,7 +8,7 @@ import EditorIcon from '../components/EditorIcon'
 import SectionTitle from '../components/SectionTitle'
 import ChatSidebar from '../components/ChatSidebar'
 import LiveFeed from '../components/LiveFeed'
-import { editorColor, editorLabel, formatNumber, formatDate } from '../lib/constants'
+import { editorColor, editorLabel, formatNumber, formatCost, formatDate } from '../lib/constants'
 import { fetchRelayTeamStats, fetchRelaySearch, fetchRelaySession, mergeRelayUsers } from '../lib/api'
 import AnimatedLoader from '../components/AnimatedLoader'
 import PageHeader from '../components/PageHeader'
@@ -331,6 +331,7 @@ export default function RelayDashboard() {
           <KpiCard label="projects" value={stats.totalProjects} />
           <KpiCard label="messages" value={formatNumber(stats.totalMessages)} />
           <KpiCard label="tokens" value={formatNumber(totalTok)} sub={`${formatNumber(tokPerSession)}/session`} />
+          <KpiCard label="total cost" value={formatCost(stats.totalCost)} sub="estimated" />
         </div>
 
         {/* Token overview */}
@@ -525,12 +526,13 @@ export default function RelayDashboard() {
                     ))}
                   </div>
                 </div>
-                <div className="grid grid-cols-4 gap-1 text-center mb-2">
+                <div className="grid grid-cols-5 gap-1 text-center mb-2">
                   {[
                     [u.sessions, 'sessions'],
                     [formatNumber(u.totalMessages), 'messages'],
                     [u.projects, 'projects'],
                     [formatNumber(uTok), 'tokens'],
+                    [formatCost(u.totalCost), 'cost'],
                   ].map(([v, l]) => (
                     <div key={l} className="p-1 rounded-sm" style={{ background: 'var(--c-code-bg)' }}>
                       <div className="text-[11px] font-bold" style={{ color: 'var(--c-white)' }}>{v}</div>