Limits and quotas | Faustine Docs

Limits cap how much a credential can call through a gateway environment. They are set for the environment in the gateway's Policies tab, and a key or user can set lower values on its own page.

Usage

An environment's limits apply to every key and user of that environment. Each credential is counted on its own: a limit of 600 requests per minute means 600 for each key, not 600 for all of them. A field left empty uses the default in the tables on this page.

A key or user can only set a value lower than its environment's. The portal refuses a higher value when you save. For a gateway user, the limits are shared by all of that user's sessions.

Each environment has its own limits. A new environment starts with a copy of the limits of the one it was created from.

Rate limit

Field	Default	Description
Requests / minute	600	Sustained rate per credential.
Burst	100	How many calls can arrive at once before the rate applies.

A call over the rate is refused with rate_limit and a Retry-After header.

Environment-wide rate limit

Field	Default	Description
Requests / minute, all credentials	None	One count shared by every key and user of the environment. It is the most your API receives in total.

This limit exists only on the environment. A call over it is refused with rate_limit and a Retry-After header.

Quota

Field	Default	Description
Calls / hour	10,000	Calls per credential in a clock hour.
Calls / day	50,000	Calls per credential in a day. The day starts at 00:00 UTC.

A call over a quota is refused with quota. Retry-After is the number of seconds until the hour or the day ends. A refused call does not count toward the quota.

Concurrency

Field	Default	Description
Max concurrent calls	8	Calls in flight per credential at one moment.

A call over the limit is refused with concurrency and Retry-After: 1.

Request limits

Field	Default	Description
Max body (KB)	1024	Size of a REST body or of the arguments of an MCP call.
run_code max seconds	30	Run time of one Code mode script.
run_code memory (MB)	128	Memory of one script.
run_code max ops	200	Operation calls one script can make.

The three run_code defaults are also the maximum. A body over the limit is refused with body_too_large.

Channels

Field	Default	Description
MCP	On	Whether the MCP endpoint can be used.
REST	On	Whether the REST mirror can be used.

A call on a channel that is off is refused with channel. A credential can use only the channels its environment serves.

Validity

These two fields exist only on a key or a user.

Field	Default	Description
Not before	Valid immediately	The credential is refused until this date.
Expires	Never	The credential is refused after this date. A user can no longer sign in, and their sessions stop working.

Errors

Over REST, a refused call returns the status in this table and a body with the code. Over MCP, the tool call fails with the text Denied (<code>): <message>.

Code	HTTP status	`Retry-After`	Cause
`rate_limit`	429	Yes	The credential's rate or the environment-wide rate was exceeded.
`quota`	429	Yes	The hourly or daily quota is used up.
`concurrency`	429	Yes	Too many calls in flight.
`runner_busy`	429	Yes	The script could not start because the code runner is at capacity.
`body_too_large`	413	No	The body or the arguments exceed Max body (KB).
`channel`	403	No	The credential or the environment does not allow this channel.

A credential outside its validity window gets 401, with Denied (not_yet_valid) or Denied (expired) in the message.

Every refusal is a request in the gateway's Logs tab with its reason. The Overview tab shows the number of denied requests in the last 24 hours and the most frequent reason.

Other limits

Limit	Value
Failed authentications from one IP address	30 per minute. Further requests from that address get `429` with the code `auth_throttled` until the minute ends.
Failed sign-ins of a gateway user	5. The user is locked for 15 minutes.
Result of a Code mode script	1 MB
Time a connection has to answer under fan-out routing	20 seconds
Window for repeated writes	1 to 86,400 seconds. The default is 60.
Variables per environment	100

Next steps

Restrict access by IP address: the allowlist, the blocklist and blocked countries.
Gateway HTTP: the error envelope and every error code.
Limits: the limits of the rest of the platform.