System-Prompt-Judge Routing¶

system_prompt_judge serves every caller-visible turn with one target, but first asks a judge model whether to inject one hidden system prompt from a text DB.

Use it for small experiments where a reviewer should choose from a fixed set of interventions without exposing those interventions to the served agent unless one is selected.

Configuration¶

[targets.primary]
id = "model/agent"
llm_client = "upstream"

[targets.judge]
id = "model/judge"
llm_client = "upstream"

[routes.agent]
id = "switchyard/agent"
type = "system_prompt_judge"
target = "primary"
judge_target = "judge"
db_path = "actions.txt"

db_path is resolved relative to the TOML file when the server loads the deployment from disk. Absolute paths also work.

The action DB is a plain text file with one [action_id] section per prompt:

[compile_failure]
Focus on the exact compiler error before editing code.

[stuck_loop]
Stop repeating the same command. Make a new hypothesis and test it.

For each request, the judge sees the conversation plus the hidden action DB and returns:

{"action":"compile_failure"}

or:

{"action":"none"}

If the judge chooses a known action, Switchyard prepends that action's text as a system instruction on the call to target. If the judge fails, returns invalid JSON, returns none, or selects an unknown action, the route fails open and sends the original request to target.

Route keys¶

Key	Required	Default	Meaning
`target`	Yes	—	Target that serves the caller-visible request.
`judge_target`	Yes	—	Target used to choose one action id or `none`. Not a routing destination.
`db_path`	Yes	—	Text DB containing `[action_id]` prompt sections. Relative paths resolve next to the TOML file.
`max_output_tokens`	No	`64`	Maximum completion tokens for the judge verdict.