Open in the interactive docs · markdown for agents: https://neuraldeep.tech/docs/limits.md

Limits and error codes

Chat models have four limits at once: session (3-hour UTC window), week (ISO week), concurrency (requests in flight at the same time) and requests per minute. Any of them yields 429; retry according to the specific reason. The higher the plan, the wider all four. A key sees its own remainders in GET /v1/limits; the general error table is in getting started.

For an agent 429, check which window fired. Start with client setup, then use the settings builder and your profile notes. There is no universal concurrency field for every client.

Headers on our 429s:

Free plan input cap. On the Free plan a single chat request is capped at 46,112 input tokens, counting both messages and tool schemas. This is a plan cap, not a model property: the catalog shows the model window (262,144 for qwen3.6-35b-a3b). A longer request gets a 400:

{"error": {"message": "Слишком длинный запрос: 52000 токенов входа при пределе 46112 на бесплатном тарифе. Считаются и сообщения, и схемы инструментов... (maximum context length is 46112 tokens)", "code": "400"}}

(The message is in Russian: "Request too long: N input tokens over the 46112 limit on the Free plan"; the English tail lets agents detect context overflow.) Your key's effective window is in GET /v1/models: limit.context already accounts for the plan. When the plan cuts the window, limit.context_model (the full model window) and limit.context_reason: "tier" sit next to it. An agent should take the number from here, not from the model table.

curl -s https://api.neuraldeep.tech/v1/models -H "Authorization: Bearer $YOUR_KEY" \
  | jq '.data[] | select(.id=="qwen3.6-35b-a3b") | .limit'

The cap applies only to a key in Plan mode. A key in Wallet mode and any paid plan get the model's full window. A common trap: the wallet is topped up, but the key is still in Plan mode and keeps living by Free rules. The mode is switched per key on the API keys page.

Example 429 bodies:

// X-Window: session, the 3-hour limit is used up
{"error": {"message": "Your plan's 3-hour request limit is used up. Paused until 15:00 UTC. Reset the limit now: https://hub.neuraldeep.tech/app/resets; for more volume, a higher plan (https://neuraldeep.tech/en/pricing) or switch the key to Wallet mode (https://hub.neuraldeep.tech/app/keys). Limit resets at: 2026-10-22 15:00:00 UTC", "code": "429"}}

// X-Window: week
{"error": {"message": "Your plan's weekly request limit is used up, it resets on Monday 00:00 UTC. Reset the limit now: ... Limit resets at: 2026-10-26 00:00:00 UTC", "code": "429"}}

// X-Window: chat_rpm, more requests per minute than the plan allows
{"error": {"message": "Too many requests per minute (plan limit N). Retry in 58 s. Limit resets at: ...", "code": "429"}}

// X-Window: key-rpm (key-tpm, key-parallel), the key's own limit
{"error": {"message": "Key request limit per minute exceeded. Retry in 12 s. Limit resets at: ...", "code": "429"}}

// X-Window: daily-capacity
{"error": {"message": "The key's daily capacity is used up, it resets at 00:00 UTC. For more volume, a higher plan (...) or switch the key to Wallet mode (...). Limit resets at: ...", "code": "429"}}

// X-Window: abuse, the client kept hammering after a refusal
{"error": {"message": "Requests from this account are paused for 60 min: the client retried many times in a row after being refused by a limit. Wait as long as the Retry-After header says before retrying. Limit resets at: ...", "code": "429"}}

To avoid the pause for repeated retries, retry only after Retry-After. Texts come in the key owner's dashboard language (or by Accept-Language); the Limit resets at: tail is always the same.

Model gateway response codes:

Reference sections (markdown for agents)