1.66.0

New Features

• Add Lapdog cost tracking for Claude Fable 5.1, Claude Mythos 5.1, and GPT-6 Astra. Includes Claude models' reduced cache-read rate and long-context pricing for GPT-5.6 and Astra. For GPT-5.6 Sol models, costs are tracked at promotional pricing rates documented through November 21, 2026.
• Lapdog: Adds --version and --help flags for the lapdog CLI (e.g. lapdog --version).

Deprecation Notes

• The ddapm-test-agent --lapdog-mode entry point is deprecated, use python -m lapdog.server instead (including in Docker commands). The preferred way of using Lapdog is via the CLI lapdog binary. It remains available as a compatibility alias.

Bug Fixes

• LLMObs spans whose payload uses the flat meta["span.kind"] form (instead of the nested meta["span"]["kind"] form the ddtrace LLMObs writer emits today) now have their kind preserved through the lapdog UI trace and list endpoints. Previously tool, agent, workflow, retrieval, and embedding spans submitted in the flat form were silently rendered as kind="llm".
• Fix Codex missing session inputs in Lapdog.
• Prevent lapdog codex from capturing unrelated Codex sessions in the same working directory.
• Fix truncated trace responses when proxying to a real agent via DD_AGENT_URL. The forwarded body is re-serialized with json.dumps, making it longer than the agent's compact JSON, but the agent's Content-Length was relayed verbatim. The response was cut to that length and tracers failed to parse it. The headers describing the original encoding are now recomputed from the body actually sent.