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You don’t need every span. Filter out the noise and ship the useful bits. LangWatch lets you keep AI and business spans while dropping framework chatter.
Introduced in [email protected].

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Defaults

By default we exclude HTTP request spans. 
import { setupObservability } from "langwatch/observability/node";
import { LangWatchTraceExporter } from "langwatch";

setupObservability({
  // We are specifying a custom trace exporter, so we need to disable default
  // integration to prevent double exporting
  langwatch: "disabled",
  traceExporter: new LangWatchTraceExporter(),
});
Default is equivalent to { filters: [{ preset: "excludeHttpRequests" }] }. You can set filters: null or filters: [] to send all spans.

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Quick start

new LangWatchTraceExporter({ filters: [] });

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Custom filters

Use include to keep matches; use exclude to drop matches. Criteria support:
  • instrumentationScopeName
  • name
// Keep only spans from the 'ai' scope
new LangWatchTraceExporter({
  filters: [{ include: { instrumentationScopeName: [{ equals: "ai" }] } }]
});

// Drop internal spans by name prefix
new LangWatchTraceExporter({
  filters: [{ exclude: { name: [{ startsWith: "internal." }] } }]
});

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Matching

Matchers are case-sensitive unless you set ignoreCase: true. 
// equals (exact)
{ name: [{ equals: "chat.completion" }] }

// startsWith (prefix)
{ name: [{ startsWith: "chat." }] }

// matches (RegExp)
{ name: [{ matches: /^(GET|POST)\b/ }] }

// case-insensitive
{ name: [{ equals: "Chat.Completion", ignoreCase: true }] }

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Logic

  • OR within a field: multiple matchers are alternatives
  • AND across fields: all specified fields must match
// name starts with chat. OR llm.
{ include: { name: [{ startsWith: "chat." }, { startsWith: "llm." }] } }

// scope is ai AND name starts with chat.
{ include: { instrumentationScopeName: [{ equals: "ai" }], name: [{ startsWith: "chat." }] } }

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Pipelines (sequential AND)

Filters run in order; each step narrows the set. 
new LangWatchTraceExporter({
  filters: [
    { include: { instrumentationScopeName: [{ equals: "ai" }] } },
    { preset: "excludeHttpRequests" },
    { exclude: { name: [{ matches: /test/ }] } }
  ]
});

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Integrate with setupObservability

import { setupObservability } from "langwatch/observability/node";
import { LangWatchTraceExporter } from "langwatch";

setupObservability({
  // We are specifying a custom trace exporter, so we need to disable default
  // integration to prevent double exporting
  langwatch: "disabled",
  traceExporter: new LangWatchTraceExporter({
    filters: [{ preset: "excludeHttpRequests" }]
  })
});
Via BatchSpanProcessor
import { setupObservability } from "langwatch/observability/node";
import { BatchSpanProcessor } from "@opentelemetry/sdk-trace-base";
import { LangWatchTraceExporter } from "langwatch";

setupObservability({
  // We are specifying a custom trace exporter, so we need to disable default
  // integration to prevent double exporting
  langwatch: "disabled",
  spanProcessors: [
    new BatchSpanProcessor(
      new LangWatchTraceExporter({ filters: [{ preset: "vercelAIOnly" }] })
    ),
  ],
});

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Troubleshooting

  • Nothing exported: try filters: [], then add rules back
  • Too much noise: apply excludeHttpRequests, add specific exclude rules
  • Case surprises: add ignoreCase: true where needed
  • Check values: log span.name and span.instrumentationScope.name in dev

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Types

import type { TraceFilter, Criteria, Match } from "langwatch";
Use simple matchers (equals, startsWith) where possible; regex is powerful but slower and harder to read.