Xcatcher (x402 + Tasks)

Use this skill to:

• buy points via x402 on Solana (USDC),
• obtain an API key,
• create crawl tasks,
• poll task status,
• download XLSX results.

Base URL: https://xcatcher.top
REST base: https://xcatcher.top/api/v1
Optional health: https://xcatcher.top/mcp/health

Requirements

• curl, jq, base64
• Set XCATCHER_API_KEY for authenticated calls (you will obtain it in step 4 if you don't have one).

Points pricing (task cost)

• mode=normal: 1 point / user
• mode=deep: 10 points / user
• estimated_cost = users_count × (mode == normal ? 1 : 10)
• support chain: base / sol

Do not hardcode any USDC→points rate. Always trust the quote response.

---

0) Optional health check

BASE="https://xcatcher.top" curl -sS "$BASE/mcp/health" echo

---

1) Get an x402 quote (points → Solana USDC payment instructions)

Notes:

• Quotes expire quickly (often ~60s). Pay immediately after receiving the quote.

BASE="https://xcatcher.top" POINTS=1

curl -sS "$BASE/api/v1/x402/quote?points=$POINTS" | tee quote.json echo

QUOTE_ID=$(jq -r '.quote_id' quote.json) USDC_MINT=$(jq -r '.accepts.solana.asset' quote.json) PAY_TO=$(jq -r '.accepts.solana.payTo' quote.json) AMOUNT_ATOMIC=$(jq -r '.accepts.solana.maxAmountRequired' quote.json)

echo "QUOTE_ID=$QUOTE_ID" echo "USDC_MINT=$USDC_MINT" echo "PAY_TO=$PAY_TO" echo "AMOUNT_ATOMIC=$AMOUNT_ATOMIC" echo "USDC_AMOUNT=$(python3 - <<'PY' import json q=json.load(open("quote.json")) amt=int(q["accepts"]["solana"]["maxAmountRequired"]) print(amt/1_000_000) PY )" echo

QUOTE_ID must save

2) Pay USDC on Solana mainnet

Send USDC (SPL) to PAY_TO for at least AMOUNT_ATOMIC (USDC has 6 decimals).
Record the Solana transaction signature, then set it below.

SOL_SIG="YOUR_SOLANA_TX_SIGNATURE"

---

3) Build PAYMENT-SIGNATURE header (base64 of UTF-8 JSON)

Rules:

• Base64 encode once (no double encoding).
• Do not wrap the header value in extra quotes.

PAYMENT_SIGNATURE_B64=$(jq -nc --arg sig "$SOL_SIG"
'{"x402Version":1,"scheme":"exact","network":"solana:mainnet","payload":{"signature":$sig}}'
| base64 | tr -d '\n')

echo "PAYMENT_SIGNATURE_B64=$PAYMENT_SIGNATURE_B64" echo

---

4) Buy points (quote_id + PAYMENT-SIGNATURE → api_key)

BASE="https://xcatcher.top"

curl -sS -X POST "$BASE/api/v1/x402/buy_points"
-H "Content-Type: application/json"
-H "PAYMENT-SIGNATURE: $PAYMENT_SIGNATURE_B64"
-d "$(jq -nc --arg q "$QUOTE_ID" '{quote_id:$q}')"
| tee buy.json echo

API_KEY=$(jq -r '.api_key' buy.json) echo "API_KEY=$API_KEY" export XCATCHER_API_KEY="$API_KEY" echo "XCATCHER_API_KEY exported." echo

---

5) Verify balance (must-do)

BASE="https://xcatcher.top" curl -sS "$BASE/api/v1/me"
-H "Authorization: Bearer $XCATCHER_API_KEY"
| jq . echo

If you get 402 here or later:

• Most common causes: quote expired or payment proof invalid.
• Fix: redo steps 1 → 4 with a NEW quote and NEW payment.

---

6) Create crawl task

Rules:

• users are X usernames without '@'
• always provide idempotency_key
• if retrying the same logical request, reuse the same idempotency_key

BASE="https://xcatcher.top" MODE="normal" IDEM="test-idem-001" USERS_JSON='["user1","user2"]'

echo "ESTIMATED_COST_POINTS=$(python3 - <<'PY' import json, os users=json.loads(os.environ.get("USERS_JSON","[]")) mode=os.environ.get("MODE","normal") per=1 if mode=="normal" else 10 print(len(users)*per) PY )" echo

curl -sS -X POST "$BASE/api/v1/tasks"
-H "Authorization: Bearer $XCATCHER_API_KEY"
-H "Content-Type: application/json"
-d "$(jq -nc --arg mode "$MODE" --arg idem "$IDEM" --argjson users "$USERS_JSON"
'{mode:$mode, users:$users, idempotency_key:$idem}')"
| tee task.json | jq . echo

TASK_ID=$(jq -r '.task_id' task.json) echo "TASK_ID=$TASK_ID" echo

---

7) Poll task status until ready

Stop when download_url or result_path is present.

BASE="https://xcatcher.top" while true; do J=$(curl -sS "$BASE/api/v1/tasks/$TASK_ID" -H "Authorization: Bearer $XCATCHER_API_KEY") echo "$J" | jq '{task_id,status,status_code,updated_time,error_message,result_path,download_url}' HAS=$(echo "$J" | jq -r '(.download_url // .result_path // "") | length') if [ "$HAS" -gt 0 ]; then echo "DONE" break fi sleep 5 done echo

---

8) Download result (XLSX)

Download requires the same Bearer token; results are not public.

BASE="https://xcatcher.top" curl -sS -L -o "task_${TASK_ID}.xlsx"
-H "Authorization: Bearer $XCATCHER_API_KEY"
"$BASE/api/v1/tasks/$TASK_ID/download"

echo "Saved: task_${TASK_ID}.xlsx" echo

---

Failure handling

• 401: Bearer token missing/invalid → obtain API key via buy_points or set XCATCHER_API_KEY correctly.
• 402: quote/proof invalid or expired → redo quote + pay + buy_points (steps 1–4).
• 429: rate limited → backoff; respect Retry-After if present.
• Task stuck / upstream issues → report clearly; poll with increasing interval if needed.