Top 100 AI Agent Architecture Design Concepts

39 — Content Moderation API

Integrate content classification as a versioned policy service with explicit thresholds, contextual handling, latency budgets, and review paths.

Concept overview

A content moderation API classifies submitted material into policy-relevant categories or returns associated scores. The application decides what those classifications mean for its audience and workflow. Provider labels and confidence scores are not universal legal judgments, and thresholds should be validated against representative content.

Moderation can apply to user inputs, retrieved material, generated outputs, and uploaded media. Each surface has a different purpose: rejecting a user action, quarantining evidence, or controlling publication. Keep moderation separate from malware scanning, authorization, and factual verification, which address different failure modes.

Why it matters in production

Proof of concept

A prototype can score a reviewed sample and inspect false positives before enabling automatic blocking. Include legitimate discussion of sensitive topics.

Production

Production versions the moderation policy, maps provider categories to application outcomes, and defines timeouts and outage behavior. Minimize the personal data sent to the classification service.

Enterprise scale

At scale, asynchronous review, multilingual evaluation, and drift monitoring become necessary. Measure disagreement and appeals rather than assuming the provider's default thresholds fit every tenant or product.

Architecture components

Content adapter

Normalizes supported text and media while preserving the context needed for classification.

Moderation service

Produces category signals under a known model or API configuration.

Policy mapper

Converts signals into allow, block, quarantine, or review outcomes for the application.

Review workflow

Handles ambiguous cases, appeals, and high-impact decisions with accountable human judgment.

Moderation telemetry

Tracks latency, errors, decision rates, and reviewed false positives without excessive content retention.

The architecture, mapped

Classification becomes an application policy decision — The API supplies signals; the application owns the action and the process for uncertain cases.
flowchart LR
 C["Text or media content"] --> A["Content adapter"]
 A --> M["Moderation API"]
 M --> P["Application policy mapper"]
 X["Audience and workflow context"] --> P
 P --> L["Allow"]
 P --> B["Block or quarantine"]
 P --> H["Human review"]
 H --> E["Reviewed evaluation data"]

Runtime flow

  1. 1

    Identify surface

    Determine whether the content is input, evidence, output, or an uploaded asset.

  2. 2

    Prepare payload

    Apply size limits, data minimization, and format handling appropriate to the service.

  3. 3

    Request classification

    Call the API with a deadline and record its version and operational status.

  4. 4

    Apply policy

    Map category signals and context to explicit application decisions.

  5. 5

    Handle uncertainty

    Route borderline or unsupported content to review or a defined constrained path.

  6. 6

    Evaluate decisions

    Compare sampled outcomes with reviewed labels and update thresholds through controlled changes.

Reviewing seller-generated product descriptions

Online marketplace · Illustrative enterprise scenario, not a reported customer outcome.

Business situation

A marketplace lets sellers use an assistant to draft descriptions and upload product imagery.

The problem

Generated or uploaded content can violate marketplace rules, while crude filtering rejects legitimate safety equipment and educational products.

Agent requirement

The assistant must screen publication against marketplace policy and give sellers an understandable review path.

Architecture

Input and output adapters call a moderation service, then a policy mapper combines category signals with product context.

Runtime

  • A seller submits a draft; the service scores relevant categories and the mapper decides whether to publish, request revision, or queue review.
  • A reviewer resolves ambiguous cases and records labels that support later threshold evaluation.

Failure scenario

If the moderation API times out, unpublished high-risk content remains pending under the defined policy instead of silently bypassing screening.

Operational impact

Track reviewed violation rate, false rejections, appeal outcomes, moderation latency, and pending-review age by content type and language.

Architecture tradeoffs

DecisionBenefitCost
External moderation APISpecialized classification can be integrated quickly.Latency, data handling, and provider changes become dependencies.
Automatic blockingClear violations can be handled at volume.False positives can unfairly interrupt legitimate users.
Human reviewContext-sensitive decisions can be corrected.Review capacity and response time limit throughput.

Failure scenarios & recovery

A provider changes category behavior

Detect: Decision-rate drift and reviewed samples reveal a shift.

Recover: Recalibrate the mapping and version the policy change.

Unsupported media bypasses classification

Detect: Adapter coverage checks identify an unprocessed format.

Recover: Reject, transform safely, or route the asset to review.

Common architecture mistakes

Using provider scores as universal thresholds

Calibrate against application-specific reviewed examples.

Applying identical policy to evidence and publication

Define separate handling for each surface.

Failing open accidentally during API errors

Specify and test outage behavior explicitly.

When to choose this pattern

Choose it when

  • User or generated content needs policy-based screening.
  • Clear application outcomes can be mapped from category signals.
  • Ambiguous cases have a review or appeal path.

Avoid it when

  • The requirement is malware detection or authorization alone.
  • No representative content exists for calibration.
  • The service's data handling conflicts with approved processing rules.

Architecture checklist

  • Define policies for each content surface.
  • Calibrate thresholds with reviewed examples.
  • Version provider configuration and mappings.
  • Set request deadlines and outage behavior.
  • Cover supported languages and media formats.
  • Measure appeals and false-positive burden.

Primary references