`reyn config`¶

Inspect and modify the effective Reyn configuration.

Synopsis¶

reyn config [show]
reyn config fields
reyn config get <key>
reyn config set <key> <value>
reyn config validate
reyn config migrate [--dry-run]
reyn config migrate-mcp [--dry-run]

Subcommands¶

Subcommand	Description
`show`	Print effective merged configuration as YAML (default).
`fields`	List all known keys with types and defaults.
`get <key>`	Print the value of a single dot-path key.
`set <key> <value>`	Write a key to `reyn.local.yaml`. Value is parsed as YAML.
`validate`	Report unrecognized/renamed keys (policy tier + the hot-reload IN-set) and known keys currently disabled by another key's value. Never fails the exit code — see Notes.
`migrate [--dry-run]`	Rewrite renamed top-level config keys to their current location, in place, in whichever file each was found. Also reports (never auto-deletes) any REMOVED key with no successor — #4375.
`migrate-mcp [--dry-run]`	Move legacy `mcp.servers` entries out of `reyn.yaml`/`reyn.local.yaml`/`~/.reyn/config.yaml` into `.reyn/mcp.yaml` (#470 config separation).

Exit codes¶

Code	Meaning
`0`	Success — including `validate` reporting findings (see Notes).
`1`	Unknown key (`get`/`set`), no project root found (`migrate-mcp`), or I/O error.

Notes¶

reyn config set always writes to reyn.local.yaml (gitignored) — never to reyn.yaml.

reyn config validate always exits 0, even when it reports findings — it REPORTS, it never gates (owner ruling: warn, never hard-fail, anywhere). It checks six things, each printed as its own labeled section (never merged into one list — the fix differs per section, and merging would lose "which one do I fix, and how"). Note the last three checks (hook entries, MCP server placement, MCP transport type) each cover multiple separate config files under one section, not one:

Unrecognized/renamed/removed keys, policy tier (reyn.yaml / reyn.local.yaml / ~/.reyn/config.yaml) — the same check load_config's own startup warning runs. Fix: edit the file and restart, or run reyn config migrate for a renamed key with an automatic destination. A REMOVED key (#4375 — no successor exists, unlike a rename) is reported in its own "REMOVED ... delete them" section — migrate never auto-rewrites it (there is no destination) and never auto-deletes it either; the operator's next action is "delete this line", not "rewrite it".
Known keys currently disabled by another key's value — the key is real and correctly spelled, but the current configuration makes it a no-op (e.g. tool_use.universal_wrappers_enabled has no effect while tool_use.scheme resolves to enumerate-all — both fields live under the same tool_use: block since #4552 PR-3+4 moved universal_wrappers_enabled out of the now-deleted action_retrieval: section). Each entry names the key it depends on and the fix.
Unrecognized/renamed/removed keys, the hot-reload IN-set (.reyn/{mcp,cron,hooks,skills, pipelines,presentations}.yaml) — same unknown-key check, run against the merged IN-set instead of the policy tier. Fix: edit the .reyn/*.yaml file directly — it applies on the next turn automatically, no restart and no reyn config migrate support for this tier (a different remedy than the policy tier above, which is exactly why this is its own section).
Hook entry validation, all three real hooks: input paths (#4501 / #4364 PR-1) — the top-level unknown-key checks above only confirm hooks: itself is a recognized key; they never recurse into what each list entry contains. This section feeds every real hooks source through the real load_hooks parser (the SAME parser hook-loading itself uses) and reports any HookConfigError (e.g. an unrecognized or wrong-scope per-hook key), labeled by source:
- reyn.yaml's own top-level hooks: — the startup layer, and the one the hooks guide tells operators to write in. #4501 did not cover this source.
- .reyn/config/hooks.yaml — the runtime IN-set (#4501's own original fix).
- every .reyn/agents/<name>/hooks.yaml — the per-agent layer, one finding per agent directory that has a malformed entry. Fix: edit the offending hook entry in whichever labeled file the finding names.
MCP server placement (#4631) — the same class of gap as hook entries above, for a different config surface: unknown_config_keys confirms mcp: itself is a recognized key but never opens what's under it, so a server entry written directly at mcp.<name> (instead of mcp.servers.<name>) loads WITHOUT error and WITHOUT warning — cfg.mcp.servers silently stays empty and the server is never registered. Detected by shape (a dict directly under mcp:, other than the real servers key, carrying command/url/type — a scalar config knob like mcp.timeout_seconds never takes that shape), checked PER SOURCE FILE (not the merged view the other checks above use) so the finding can name which file to fix: the same 3 static locations migrate-mcp already scans (reyn.yaml / reyn.local.yaml / ~/.reyn/config.yaml) plus the dynamic .reyn/config/mcp.yaml. Fix: add the missing servers: key by hand — migrate-mcp relocates already-correctly-nested mcp.servers entries between files, but does not add a missing servers: key to a misplaced entry.
MCP transport type (#4604) — reyn's own mcp.servers.<name>.type vocabulary renamed "http" to "streamable-http", aligning with the Agent Plugins 1.0 canonical mcp.schema.json. MCPClient already rejects the old value at connection time with a clear error naming the rename, but that only fires the next time the server is actually used — this check finds a stale type: http entry proactively, without connecting to anything, checked PER SOURCE FILE (the same 3 static locations + the dynamic .reyn/config/mcp.yaml the placement check above scans). Fix: change type: http to type: streamable-http by hand in the file the finding names.

reyn config migrate only rewrites an entry whose registered rename has an automatic destination (a plain rename, no value transform); a rename that also transforms the value is reported as "needs manual review" instead, never guessed at.

Examples¶

reyn config
reyn config fields
reyn config get safety.loop.max_router_iterations
reyn config set model strong
reyn config set safety.loop.max_router_iterations 50
reyn config validate
reyn config migrate --dry-run
reyn config migrate-mcp --dry-run

reyn config¶