A Claude Code environment variable, read out of the shipped bundle.
It has been in the build since v2.1.213, including the newest one read.
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.
Not Anthropic's. Written by Claude Opus 5.5 from reading the v2.1.286 bundle, and it can be wrong.
First seen v2.1.213 17 Jul 2026
Last seen v2.1.308 22 Oct 2026
Builds84 / 149on this box, as of v2.1.308
Written about v2.0.18 first named in a changelog, 15 Oct 2025
v2.1.213in the build not in the build never minedv2.1.308
In the changelogs
2
Releases whose published page names OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT.
The earliest release whose published evidence quoted OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT was v2.1.213, 17 Jul 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table below.
v2.1.213 – v2.1.30884 builds17 Jul 2026 → 22 Oct 2026 ◆in the build
Build by build
84
One row per release since the first build this name was read out of. Absent means the build was read and the name was not in it, never mined means no bundle for that release was ever archived, and a declared type or a default is only ever what that release's own bundle stated.
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.
