Model Upgrade

Model upgrade

A retired model id keeps answering for a few months and then stops. This skill finds every pinned id in the repository and rewrites it.

Replacement table

Each row retires the id on the left in favour of the id on the right.

Rewrite the pinned ids

Run the rewriter over the source tree. It only touches ids the table above covers, so an id it does not know is left alone for a human.

MODEL_MIGRATIONS = {
    "claude-2": "claude-sonnet-5",
    "claude-3-haiku": "claude-haiku-4-5",
    "gpt-3.5-turbo": "gpt-5-mini",
}


def migrate(model: str) -> str:
    """Return the current id for a retired one, or the id unchanged."""
    return MODEL_MIGRATIONS.get(model, model)

Check the deployment configs

The rewriter reads Python only, so deployment YAML needs a second pass. A staging config that still pins a retired id looks like this:

service: summarizer
model: claude-2
max_tokens: 4096

Point it at claude-sonnet-5 and redeploy before the retirement date.

Routing tables go stale too

A router that still names retired ids is the most common leftover, and it survives a rewrite because the ids sit in a table rather than in code:

Every id in that table is retired. Replace them with the current ids from the replacement table, then delete the fallback column — the provider routes around a busy model on its own.