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.
Maximum length of span attribute values in the bundled OpenTelemetry trace SDK; unset means no limit. Claude Code also uses the smallest of this, OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT, OTEL_LOGRECORD_ATTRIBUTE_VALUE_LENGTH_LIMIT and CLAUDE_CODE_OTEL_CONTENT_MAX_LENGTH (default 61440) as the character cap on the content it records in telemetry, such as prompts, system prompts, model output and tool inputs and results.
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
1
Releases whose published page names OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT.
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
1
BuildsHow manyDatesReading
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.
