feat: add lens_list_pairs, lens_get_pools and lens_screen_pairs tools

.changeset/mcp-lens-tools.md

@@ -0,0 +1,9 @@
+---
+'lens': minor
+---
+
+Add MCP tools `lens_list_pairs`, `lens_get_pools` and `lens_screen_pairs` (#409). Each tool calls the same
+implementation as its REST route — `/pairs`, `/pools` and `/screener` now share `listPairs`, `listPools` and
+`screenPairs` — so answers cannot drift between transports. Results are bounded by a `limit` (max 100, default
+50/50/20) and carry `nextCursor`/`hasMore` for the next page. Assets in tool results always include the full
+issuer, never a shortened form. Tool descriptions state when to use each one.

src/__tests__/pools.test.ts

@@ -7,16 +7,7 @@ vi.mock('../db', () => ({
   pgPool: { query: mockQuery },
 }))
 
-vi.mock('../redis', () => ({
-  getCachedPrice: vi.fn(),
-  setCachedPrice: vi.fn(),
-}))
-
-vi.mock('../aggregator/bestRoute', () => ({
-  getBestRoute: vi.fn(),
-}))
-
-import { registerRESTRoutes } from '../api/rest'
+import { registerPoolsRoutes } from '../routes/pools'
 import { activeNetwork } from '../config'
 
 async function buildApp(network?: 'testnet' | 'mainnet') {
@@ -27,7 +18,7 @@ async function buildApp(network?: 'testnet' | 'mainnet') {
       req.network = network
     })
   }
-  await registerRESTRoutes(app)
+  await registerPoolsRoutes(app)
   await app.ready()
   return app
 }

src/api/rest.ts

@@ -11,7 +11,6 @@ import {
   priceResponseSchema,
   routeResponseSchema,
   historyResponseSchema,
-  poolsResponseSchema,
   depthResponseSchema,
   installResponseValidation,
 } from './schemas'
@@ -219,41 +218,6 @@ export async function registerRESTRoutes(app: FastifyInstance) {
     }
   )
 
-  // GET /pools
-  //
-  // Latest snapshot per pool for one network, without reading history. The pool
-  // ids are discovered with a recursive "skip scan" over the
-  // (network, pool_id, timestamp DESC) index (jump to the next distinct pool_id
-  // each step), then one LIMIT 1 index probe per pool fetches its newest row.
-  // Cost is O(pools x log n); the old DISTINCT ON sorted every row of every
-  // network. A quiet pool is kept with its real `timestamp`, never dropped.
-  app.get('/pools', { schema: { response: { 200: poolsResponseSchema } } }, async (req) => {
-    const network = req.network ?? activeNetwork
-    const result = await pgPool.query(
-      `WITH RECURSIVE ids AS (
-         (SELECT pool_id FROM pool_snapshots WHERE network = $1 ORDER BY pool_id LIMIT 1)
-         UNION ALL
-         SELECT (SELECT s.pool_id FROM pool_snapshots s
-                  WHERE s.network = $1 AND s.pool_id > ids.pool_id
-                  ORDER BY s.pool_id LIMIT 1)
-           FROM ids
-          WHERE ids.pool_id IS NOT NULL
-       )
-       SELECT l.pool_id, l.asset_a, l.asset_b,
-              l.reserve_a::float, l.reserve_b::float, l.spot_price::float, l.fee_bp, l.timestamp
-         FROM ids
-        CROSS JOIN LATERAL (
-              SELECT * FROM pool_snapshots s
-               WHERE s.network = $1 AND s.pool_id = ids.pool_id
-               ORDER BY s.timestamp DESC
-               LIMIT 1
-             ) l
-        WHERE ids.pool_id IS NOT NULL`,
-      [network]
-    )
-    return { pools: result.rows }
-  })
-
   // GET /price/:assetA/:assetB/depth?amount=1000
   app.get<{
     Params: { assetA: string; assetB: string }

src/app.ts

@@ -7,6 +7,7 @@ import { registerGraphQL } from './api/graphql'
 import { registerWebhookRoutes } from './routes/webhooks'
 import { registerCandleRoutes } from './routes/candles'
 import { registerPairsRoutes } from './routes/pairs'
+import { registerPoolsRoutes } from './routes/pools'
 import { registerScreenerRoutes } from './routes/screener'
 import { registerHistoryRoutes } from './api/history'
 import { registerX402 } from './middleware/x402'
@@ -168,6 +169,7 @@ export async function buildApp(options: BuildAppOptions = {}): Promise<FastifyIn
   await registerWebhookRoutes(app)
   await registerCandleRoutes(app)
   await registerPairsRoutes(app)
+  await registerPoolsRoutes(app)
   await registerScreenerRoutes(app)
   await registerHistoryRoutes(app)
   await registerPriceRoutes(app)