fable51
A Claude Code settings key, read out of the shipped bundle. No mined inventory carries it: everything below comes from what this site has written about it.
The gate controlling whether the fable model is added to opus and haiku lists was renamed from fable5 to fable51.
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.257.
In the changelogs
5Releases whose published page names fable51.
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v2.1.321
New fable52 model alias
Claude Code now recognises fable52 as a model alias, next to fable51
found in this entry's text
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v2.1.260
Hidden 'fable' model surfaced only after an entitlement probe accepts
A hidden Fable model only appears once a server-side entitlement probe accepts your account.
found in this entry's text, named in this entry
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v2.1.257
Model-availability gate renamed/updated from fable5 to fable51
The gate controlling whether the fable model is added to opus and haiku lists was renamed from fable5 to fable51.
found in this entry's text, named in this entry
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v2.1.257
New model alias fable51 added
A fable51 entry joins the internal model alias list used for resolution and allowlisting.
named in this entry, found in this entry's text
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v2.1.257
claude-fable-5-1 model wiring (Vertex region + gate)
claude-fable-5-1 is wired up with its own Vertex region, and fallback lists now gate on a fable51 check.
found in this entry's text
First cited
0No 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
0The 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 settings key does. All settings keys.