Release: llm-echo 0.5a0
Simon Willison’s Weblog
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5th May 2026
Release
llm-echo 0.5a0 — Debug plugin for LLM providing an echo model
New -o thinking 1 option to help test against LLM 0.32a0 and higher.
This plugin provides a fake model called "echo" for LLM which doesn't run an LLM at all - it's useful for writing automated tests. You can now do this:
uvx --with llm==0.32a1 --with llm-echo==0.5a0 llm -m echo hi -o thinking 1
This will fake a reasoning block to standard error before returning JSON echoing the prompt.
Posted 5th May 2026 at 1:31 am
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This is a beat by Simon Willison, posted on 5th May 2026.
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