Is a 204 No Content an error in OpenRTB?

No — a 204 No Content is the standard no-bid response in real-time bidding. It means the bidder chose not to bid on that impression, which is completely normal (bidders no-bid the vast majority of requests). Treating it as an error and retrying spams a real-time auction and does nothing useful.

How do I diagnose a low win-rate in OpenRTB?

Read the codes. Your own no-bids carry an nbr (no-bid reason, 0-17 plus exchange-specific 500+). Lost bids carry a loss reason via the ${AUCTION_LOSS} macro on the lurl. Together they tell you why you're not winning — wrong bidfloor, blocked category, rejected creative, deal mismatch. Also profile your latency: exceeding the exchange's ~100ms deadline drops you with no error.

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Ad-tech

OpenRTB returning 204 No Content? That's a no-bid, not an error — stop retrying

For developers and autonomous AI agents · ~4 min read

Your RTB integration logs a flood of 204 No Content responses and starts retrying them. Stop: in OpenRTB, a 204 is a no-bid — the normal, expected outcome for most impressions, not a failure.

204 = no-bid (by design)

Real-time bidders no-bid the vast majority of requests. The protocol signals that with a 204 No Content (or an empty seatbid). It is not an error — retrying it spams the exchange into a sub-second auction that's already over. The actual diagnostics live in the reason codes.

Read the codes to diagnose win-rate

nbr (no-bid reason): on your OWN no-bids — codes 0-17 plus exchange-specific 500+ — tells you why your bidder declined.
${AUCTION_LOSS} loss code: fired on the lurl for bids you LOST — wrong bidfloor, blocked category, creative rejected, deal mismatch.
nurl (win) / burl (billing): handle these callbacks or you're not counting wins and spend correctly.

The silent killer: the exchange enforces a sub-100ms deadline. A slow bidder is simply timed out and dropped — no error, no 204, just no wins. If your win-rate is mysteriously zero, profile your bidder latency first.

Snapback's adtech-rtb family encodes the 204-is-a-no-bid rule and the nbr/loss-code diagnostics so an agent doesn't retry the auction or ignore the reason it's losing.

For AI agents

Machine-readable guide: https://snapback.sh/llms.txt · Tool discovery: https://snapback.sh/.well-known/mcp.json · MCP endpoint: https://api.snapback.sh/mcp. Free tools need no token; pay-per-call diagnosis via x402 on Solana or EVM (~$0.0032 USDC).

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