X402 X Tweet Fetcher

Buy Xcatcher points via x402 on Solana USDC, obtain an API key, create X crawl tasks, poll status, and download XLSX results.

Xcatcher (x402 + X Tasks)

Use this skill to:

• buy Xcatcher points via x402 on Solana (USDC),
• obtain an API key,
• create X 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

What this skill does

This skill provides an end-to-end flow for paid X data collection:

1. request an x402 quote for points,
2. pay the quote in Solana USDC,
3. exchange the paid quote for an API key,
4. use the API key to create crawl tasks,
5. poll task status until the result is ready,
6. download the XLSX result file.

Requirements

Local tools:

• curl
• jq
• base64

Optional:

• python3 for simple JSON math examples

Authentication:

• You do not need XCATCHER_API_KEY before starting.
• You will obtain XCATCHER_API_KEY after a successful buy_points call.
• For later authenticated calls, set:
  • export XCATCHER_API_KEY="your_api_key"

Pricing model

Task cost:

• mode=normal: 1 point per user
• mode=deep: 10 points per user

Estimated cost:

• estimated_cost = users_count × (mode == normal ? 1 : 10)

Supported payment chains:

• solana
• quote payload may also mention other supported networks if enabled by server configuration

Never hardcode any USDC-to-points conversion rate. Always trust the live quote response.

---

0) Optional health check

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

---

1) Get an x402 quote

Notes:

• quotes expire quickly,
• pay immediately after quote creation,
• save quote_id.

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

Important:

• keep QUOTE_ID,
• use it in the next purchase step,
• if the quote expires, create a new one.

---

2) Pay USDC on Solana mainnet

Send USDC (SPL) to PAY_TO for at least AMOUNT_ATOMIC.

Then record the Solana transaction signature:

SOL_SIG="YOUR_SOLANA_TX_SIGNATURE"

---

3) Build the PAYMENT-SIGNATURE header

Rules:

• base64 encode once,
• do not double encode,
• 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 and obtain an 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

BASE="https://xcatcher.top"

curl -sS "$BASE/api/v1/me" \
  -H "Authorization: Bearer $XCATCHER_API_KEY" \
  | jq .
echo

If you get 402:

• quote may have expired,
• payment proof may be invalid,
• redo steps 1 to 4 with a new quote and a new payment proof.

---

6) Create a 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"]'

export MODE USERS_JSON

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 appears.

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 the XLSX result

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 or invalid
  → obtain API key again or set XCATCHER_API_KEY correctly

• 402: quote invalid, payment proof invalid, or quote expired
  → redo quote + pay + buy_points with a fresh quote

• 429: rate limited
  → back off and respect Retry-After if present

• task delayed or upstream unavailable
  → keep polling with a longer interval and surface the error clearly

Notes for agents

• Prefer live quote responses over any cached assumptions.
• Prefer explicit idempotency_key values for retries.
• Treat task results as private and always download with the same Bearer token.
• Do not assume result files are public URLs.