Content gate: reject empty or refused responses

The content gate catches two failure modes that other gates cannot: an agent that returns nothing at all, and an agent that responds with a refusal rather than completing its assigned task. Both are treated as gate failures because they represent output that will not satisfy the user, even if the output is structurally valid. Both checks are enabled by default and can be turned off independently.

Usage

import { createEngine, gates } from "@pecta/core";

const engine = createEngine({
  gates: [
    gates.content(),
  ],
});

const result = await engine.evaluate({
  agent_id: "assistant",
  output: "I'm just an AI and I can't help with that.",
});
// result.passed === false

Empty output detection

The gate considers ctx.output empty if it is any of the following:

undefined or null
A string containing only whitespace (or an empty string)
An empty array ([])
An object with no own keys ({})

Any other value — including false, 0, or a non-empty string — is treated as non-empty.

AI refusal phrase detection

The gate scans every string in ctx.output for phrases that indicate the model is declining to fulfill the request rather than producing useful output. The following patterns are matched case-insensitively:

Pattern	Example phrase
`i don't have access` / `i do not have access`	”I don’t have access to real-time data.”
`i don't have the ability` / `i do not have the ability`	”I don’t have the ability to browse the web.”
`i can't do` / `i cannot do`	”I cannot do that.”
`i can't help` / `i cannot help`	”I can’t help with this request.”
`i can't provide` / `i cannot provide`	”I cannot provide personal advice.”
`i can't access` / `i cannot access`	”I can’t access external systems.”
`i can't complete` / `i cannot complete`	”I cannot complete this task.”
`i can't fulfill` / `i cannot fulfill`	”I can’t fulfill that request.”
`i can't assist` / `i cannot assist`	”I cannot assist with that.”
`as an ai language model`	”As an AI language model, I…”
`as an ai model`	”As an AI model, I…”
`i'm an ai` / `i am an ai` / `i'm just an ai`	”I’m just an AI.”

The gate returns passed: false on the first match it finds. It does not enumerate all matching phrases.

What a failure looks like

{
  "name": "content",
  "passed": false,
  "reason": "output contains refusal/disclaimer",
  "latency_ms": 0.17
}

{
  "name": "content",
  "passed": false,
  "reason": "output is empty",
  "latency_ms": 0.06
}

Configuration

boolean

Fail evaluations where ctx.output is empty, whitespace-only, an empty array, or an empty object. Defaults to true.

boolean

Fail evaluations where any string in ctx.output matches a known AI refusal or disclaimer phrase. Defaults to true.

string

Override the gate name recorded in results. Defaults to "content".

Disabling a check

import { createEngine, gates } from "@pecta/core";

const engine = createEngine({
  gates: [
    gates.content({
      rejectEmpty: true,
      rejectRefusals: false, // agent may legitimately explain its constraints
    }),
  ],
});

Place gates.content() early in your gate list. With failFast: true (the default), detecting an empty or refused output immediately aborts the remaining gates — avoiding schema validation and PII scanning on output that you are going to reject anyway.

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Core Concepts

Gates

RTB Gates

Dashboard

Content gate: reject empty or refused responses

Usage

Empty output detection

AI refusal phrase detection

What a failure looks like

Configuration

Disabling a check

​Usage

​Empty output detection

​AI refusal phrase detection

​What a failure looks like

​Configuration

​Disabling a check

Usage

Empty output detection

AI refusal phrase detection

What a failure looks like

Configuration

Disabling a check