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`OTEL_SERVICE_NAME`

env never mined JSON

A Claude Code environment variable, read out of the shipped bundle. No mined inventory carries it: everything below comes from what this site has written about it.

You can now set OTEL_SERVICE_NAME, OTEL_TRACES_EXPORT_INTERVAL and CLAUDE_CODE_FORK_SUBAGENT in settings.json.

Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.232.

First seen — never in a mined build

Last seen — never in a mined build

Builds0 / 149on this box, as of v2.1.308

Written about v2.1.232 first named in a changelog, 13 Aug 2026

In the changelogs

Releases whose published page names OTEL_SERVICE_NAME.

v2.1.232 13 Aug 2026
Three more variables can be set from settings.json
You can now set OTEL_SERVICE_NAME, OTEL_TRACES_EXPORT_INTERVAL and CLAUDE_CODE_FORK_SUBAGENT in settings.json.

named in this entry, found in this entry's text

First cited

No release's published evidence quotes this name. The ledger indexes the Evidence lines of every changelog on this site, so this says nobody here has ever quoted it; it says nothing about how old the name is.

Presence across releases

The miner has never read a build containing this name. It is here because a changelog entry of ours names it, which is evidence that it existed and not evidence of which releases carried it. The inventory starts at v2.1.138 and everything older than that was never mined.

Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the environment variable does. All environment variables.

Names beside it

Every environment variable in the inventory starting otel, up to twelve of them.

OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT v2.1.213
Claude Code caps the content it records in telemetry (prompts, system prompts, model output, tool inputs and results) at the smallest of this, OTEL_LOGRECORD_ATTRIBUTE_VALUE_LENGTH_LIMIT, OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT and CLAUDE_CODE_OTEL_CONTENT_MAX_LENGTH (default 61440), cutting longer content and appending a [TRUNCATED - Content exceeds ... limit] marker. The bundled OTel SDK reads it only as a fallback for the log record and span attribute limits, which its own defaults always fill (unlimited when their variables are unset), so it does not limit SDK attributes.
OTEL_EXPORTER_OTLP_ENDPOINT v2.1.138
Base URL for OTLP telemetry exports. When no signal-specific OTEL_EXPORTER_OTLP_<SIGNAL>_ENDPOINT is set, the HTTP exporters send to this URL with /v1/metrics, /v1/logs or /v1/traces appended, and the gRPC exporter uses it as given. Claude Code also reads it to pick the exporter's proxy and TLS agent options and in its gateway telemetry routing checks, and its gateway's managed settings set it to listen.public_url when telemetry.forward_to is configured.
OTEL_EXPORTER_OTLP_HEADERS v2.1.138
Telemetry exporters can now ignore OTEL_EXPORTER_OTLP_HEADERS and use only the headers given in configuration
OTEL_EXPORTER_OTLP_INSECURE v2.1.138
Used by the OTLP gRPC exporter when the endpoint starts with neither http:// nor https://: true (case-insensitive, trimmed) uses insecure credentials, any other value uses TLS credentials. A non-empty signal-specific OTEL_EXPORTER_OTLP_<SIGNAL>_INSECURE takes precedence; http:// endpoints are always insecure and https:// endpoints always use TLS.
OTEL_EXPORTER_OTLP_LOGS_ENDPOINT v2.1.160
URL for OTLP log exports, used as given without a /v1/logs suffix and taking precedence over OTEL_EXPORTER_OTLP_ENDPOINT. Claude Code also reads it to pick the log exporter's proxy and TLS agent options and when matching the endpoint against a collector named by gateway managed settings.
OTEL_EXPORTER_OTLP_LOGS_HEADERS v2.1.229
Comma-separated key=value headers for OTLP log exports; the bundled exporters merge it over OTEL_EXPORTER_OTLP_HEADERS, its values winning on a clash. While it is set, Claude Code skips some of its built-in routes that attach its own Authorization: Bearer token to log exports.
OTEL_EXPORTER_OTLP_LOGS_PROTOCOL v2.1.138
Protocol for the OTLP log exporter when OTEL_LOGS_EXPORTER includes otlp: grpc, http/json or http/protobuf. Unset or empty falls back to OTEL_EXPORTER_OTLP_PROTOCOL; any other value throws Unknown protocol set in OTEL_EXPORTER_OTLP_LOGS_PROTOCOL or OTEL_EXPORTER_OTLP_PROTOCOL env var.
OTEL_EXPORTER_OTLP_METRICS_ENDPOINT v2.1.160
In remote sessions, usage metrics can now go to the session's own metrics address, signed with CLAUDE_CODE_SESSION_ACCESS_TOKEN
OTEL_EXPORTER_OTLP_METRICS_HEADERS v2.1.229
Comma-separated key=value headers for OTLP metric exports; the bundled exporters merge it over OTEL_EXPORTER_OTLP_HEADERS, its values winning on a clash. While it is set, Claude Code skips some of its built-in routes that attach its own Authorization: Bearer token to metric exports, including the remote session ingress collector.
OTEL_EXPORTER_OTLP_METRICS_PROTOCOL v2.1.138
When metrics are sent over OpenTelemetry by gRPC or HTTP protobuf, Claude Code now prepares an extra resource before creating the exporter
OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE v2.1.138
Set OTEL_METRICS_EXPORTER=prometheus and child sessions report through the runner, giving one scrape target per machine.
OTEL_EXPORTER_OTLP_PROTOCOL v2.1.138
OTLP transport for Claude Code's telemetry exporters (metrics, logs and traces) when the signal-specific OTEL_EXPORTER_OTLP_<SIGNAL>_PROTOCOL variable is empty. Accepted values are grpc, http/json and http/protobuf; any other value, including leaving both unset, makes exporter setup throw Unknown protocol set in ... env var, and for traces one code path forces http/protobuf regardless. The claude gateway server also sets it to http/protobuf in the environment it pushes to clients through managed settings when telemetry.forward_to and listen.public_url are configured.

Documentation pages 1

Observability with OpenTelemetrymentions itClaude Code CLI

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