| name | moderate-debate |
| description | Drives a multi-agent debate from a planned agenda — builds prompts, dispatches each CLI turn into a standalone subagent, commits the shared transcript and context, handles budget/failure/checkpoint policy, and adapts the agenda mid-run when the situation diverges from the plan. Use this skill when senate has an `agenda.md` ready and needs the actual turns run, or when resuming a paused or stalled debate run. |
| license | MIT |
moderate-debate — run the debate from an agenda
You are the moderator. You did not plan the debate (the planner wrote agenda.md) and you do not synthesize the verdict (the meeting-note skill does). Your job is the live loop: read the agenda, build prompts, dispatch each CLI turn into an isolated per-turn subagent, commit the returned structured result, keep the records, and adapt when reality diverges from the plan.
A debate without a moderator is a chat. A moderator without an agenda is a chat with extra steps. Both pieces are required.
When to trigger
Activate when:
senate has an agenda.md ready and asks you to run it.- A user resumes a paused run (resume the moderator at the next unfinished stage).
- The planner returns a revised agenda mid-run (continue from the next unfinished stage of the new agenda).
Inputs
- Run directory —
<cwd>/.senate/runs/<id>/. Must already contain agenda.md with status: ready.
- (Optional) Resume signal — if non-empty
transcript.jsonl exists, resume from the last unfinished stage.
Steps
1. Pre-flight
Read agenda.md and validate:
status: ready (or revising after a re-plan).- All
cli values resolve to playbooks under ../invoke-agent/references/.
- All
format values resolve to format files under ../debate-agenda/formats/.
- All
input_bindings reference an output_bindings from an earlier stage.
If any check fails, do not start. Surface to the user via senate.
2. Initialize shared context
Each run dir contains a set of files agents read every turn (see references/context.md; full layout in ../senate/references/workspace.md):
agenda.md # the plan (already exists)
context.md # shared prompt-feed view, projection of transcript.context_delta — moderator writer
transcript.jsonl # append-only canonical per-turn record (system-only; agents never read it) — moderator writer
agents/moderator.md # moderator's governance log (you write this)
agents/<cli>.md # per-CLI private prompt-feed view, projection of transcript.private_delta — moderator writer
stages/<n>-<name>/turns/<NNN>-<cli>-<role>/prompt.derived.md # moderator writer (frozen before dispatch; see step 3.c)
stages/<n>-<name>/turns/<NNN>-<cli>-<role>/{stdout.log,stderr.log,reply.md} # per-turn subagent writer
On first start of a run:
- Create empty
context.md with a brief header explaining its purpose.
- Create empty
agents/<cli>.md for each unique CLI in the agenda.
- Create empty
agents/moderator.md with a brief header explaining it is the governance log (re-plans, contract retries, role/format swaps, tie-break rationale — every entry must cross-link the relevant turn: / stage: / incident: ID).
- Create the
stages/<n>-<name>/ directory for each stage in the agenda. Single-stage runs still get exactly one stage dir (stages/1-<format>/).
3. Walk the stages
For each stage in agenda.stages (in index order):
- Read
../debate-agenda/formats/<stage.format>.md. The format file declares roles, phases, turn order, contracts, and termination.
- Build the stage input prompt: framing wrapper + agenda body excerpt + input bindings (resolved values from prior stages).
- For each phase the format specifies:
- For each turn in the phase (sequential or parallel per the format), execute these steps in this order. Steps a–c are "freeze the prompt" and must happen before any CLI dispatch — they make the prompt-bytes ↔ sha-bytes invariant load-bearing:
- Update
state.json at every turn boundary with the new last_activity_at (atomic write: temp file + rename). Don't batch state updates to stage boundaries — a crashed or timed-out run leaves no signal of progress otherwise.
- Check budget per
references/budget.md between turns. If a cap is near, gracefully terminate and skip to the stage's synthesis turn.
- Extract the stage's
output_bindings from the verdict.
- Honor checkpoints per
references/checkpoints.md. If a required or triggered conditional checkpoint fires, write checkpoint state and pause.
4. Turn prompt construction
Every turn prompt has these sections, in this order:
- Run header — task, run_id, current stage name, format name. From
agenda.md.
- Role brief — from the format file. Who this agent is in this debate.
- Shared context — full content of
context.md. Read fresh each turn.
- Private memory — full content of
agents/<cli>.md. The agent's own scratchpad from prior turns.
- Transcript slice — prior turns this role is allowed to see (some formats redact).
- Turn instruction — what to produce this turn, including the output contract (fenced JSON) if any, and the fence labels for an optional
context-delta block (free-form prose to append to shared context) and an optional private-delta block (free-form prose to append to the agent's own memory).
The prompt string is handed to the per-turn subagent, which passes it to the CLI via stdin per ../invoke-agent/SKILL.md and wraps the call with the portable timeout command from references/budget.md.
4a. Per-turn subagent
Every turn-level CLI invocation runs inside a fresh subagent (Agent / Task tool, isolated context). The moderator never reads raw CLI stdout. If that turn needs the one permitted retry (rate_limit, timeout, exit-0 empty stdout, or contract re-prompt), the retry stays inside the same isolated subagent and is recorded as that turn's r1 attempt; retry traffic still never enters the moderator's context.
Why: debates are long. Raw CLI output, ANSI banners, re-prompt traffic, and CLI quirks would otherwise accumulate in the moderator's context, crowding out the transcript and shared scratchpad and coupling moderator stability to per-CLI failure modes. Subagent isolation also lets parallel turns actually run in parallel.
Inputs to the subagent (everything it needs — it does not see the moderator's wider state):
run_dir — absolute path to <cwd>/.senate/runs/<id>/.cli — name matching a playbook in ../invoke-agent/references/<cli>.md.turn_id — integer matching the upcoming turn field in transcript.jsonl. Used to compose the per-turn directory stages/<n>-<name>/turns/<NNN>-<cli>-<role>/ (<NNN> = turn_id zero-padded to 3 digits) where stdout.log and stderr.log land. The moderator pre-mints this directory before dispatch; the subagent only writes inside it.prompt — the full turn prompt built per "Turn prompt construction".contract — schema, example, extraction rule, re-prompt template, and an optional validators list (from the format file; full shape in references/contracts.md). validators carries free-form predicates the subagent enforces alongside schema validation — e.g., the brainstorm format's "no critique language in phase 1" rule. They run on the same shared retry path as schema validation: any predicate failure is treated as a contract violation, the subagent re-prompts once if the turn's retry budget is still available, and a second failure (or a first contract failure after a non-contract retry already consumed the budget) returns error.kind = "contract_violation". contract is null for turns with no machine validation: the subagent skips validation, sets contract_ok: true, and parsed_output: null. Free-text contracts may validate text without producing a separate parsed_output. The context-delta / private-delta extraction is independent of the contract and runs either way.timeout_seconds — per references/budget.md.
What the subagent does (and only this — files it owns are listed below; it never touches transcript.jsonl, context.md, agents/<cli>.md, state.json, agenda.md, or any stage verdict):
- Read
../invoke-agent/references/<cli>.md for the exact invocation shape.
- Shell out non-interactively, prompt on stdin, wrapped with the portable timeout command from
references/budget.md. Strip ANSI. Capture stdout to <turn-dir>/stdout.log and stderr to <turn-dir>/stderr.log, where <turn-dir> is stages/<n>-<name>/turns/<NNN>-<cli>-<role>/ (already pre-minted by the moderator). Always keep stdout.log (even when empty, so log_path always resolves); delete stderr.log only if it ended up empty ([ -s file ] || rm -f file).
- Detect non-contract errors per
references/failures.md (auth / rate_limit / timeout / refusal / unknown). On rate_limit, timeout, or exit-0 empty-stdout unknown, retry per the policy in that file before returning — the retry attempt's stdout/stderr go to <turn-dir>/stdout.r1.log / stderr.r1.log (uniform retry naming, see step 4); set retry_log_path on the return. error.kind MUST be one of the codes in that file's taxonomy.
- If the call succeeded (no error), validate against the contract per
references/contracts.md. On first parse/validate failure, re-prompt the CLI once with the re-prompt template only if the turn's shared retry budget has not already been consumed. The re-prompt call is written to <turn-dir>/stdout.r1.log / stderr.r1.log. On second failure, or on first contract failure after a non-contract retry already consumed r1, return error: { kind: "contract_violation" }. Whether the retry was triggered by rate_limit, timeout, exit-0 empty stdout, or contract validation, the file naming is the same .r1.log suffix and there is at most one retry per turn.
- Extract optional
context-delta and private-delta blocks per references/context.md. Build the cleaned reply (ANSI-stripped; fenced delta / structured-output blocks removed) and write it to <turn-dir>/reply.md; the same bytes go into the returned text field.
- Return a single structured result. No prose, no narrative, no rendered raw stdout.
Subagent return shape (fixed; moderator code reads these field names directly):
{
"contract_ok": true,
"text": "…cleaned reply, ANSI-stripped, exactly what should land in transcript.jsonl.text…",
"parsed_output": { "...": "..." },
"context_delta": "…or null…",
"private_delta": "…or null…",
"log_path": "stages/<n>-<name>/turns/<NNN>-<cli>-<role>/stdout.log",
"stderr_path": null,
"retry_log_path": null,
"retry_stderr_path": null,
"exit_code": 0,
"retry_count": 0,
"stderr_tail": null,
"duration_seconds": 42,
"error": null
}
Field rules — split by where the value lands:
Forwarded to transcript line (moderator copies into transcript.jsonl):
text — the cleaned reply (ANSI-stripped, fenced delta / structured-output blocks removed); present on every return, empty string if the CLI produced no usable stdout. Forwarded verbatim into transcript.jsonl.text and byte-identical to the <turn-dir>/reply.md the subagent writes. It is the only place cleaned reply prose enters the moderator's context, and only fleetingly during commit.parsed_output — object iff the contract declares a machine-readable structured block (usually fenced JSON) AND validation passed. null for free-text contracts that only validate the reply prose, for contract: null turns, and for any error (including contract_violation). Maps to transcript.jsonl.structured and is omitted from the transcript when null.exit_code — last CLI invocation's exit code (the retry's, if a retry happened). Maps directly.retry_count — counts CLI re-invocations the subagent performed (rate_limit, timeout, exit-0 empty-stdout unknown, or contract re-prompt — at most one retry per turn under any policy). 0 on first-try success, 1 on any retried turn.stderr_tail — last 200 bytes of stderr when error is set, else null. Already truncated by the subagent.error — null on success. Otherwise { "kind": "<code>", "detail": "..." } where <code> is one of the codes in references/failures.md (auth | rate_limit | timeout | contract_violation | refusal | unknown). The moderator imposes budget_exhausted itself before dispatching; the subagent never returns it. The moderator stores only error.kind in transcript.jsonl.error.log_path — relative path (from run dir) to the first-attempt stdout.log under the per-turn directory (e.g., stages/1-parliament/turns/007-codex-mp_pro/stdout.log). Always set; the file always exists (even when empty).retry_log_path — relative path to the retry attempt's stdout log (e.g., stages/1-parliament/turns/007-codex-mp_pro/stdout.r1.log); null when no retry happened. Naming is uniform across retry causes (rate_limit, timeout, exit-0 empty stdout, contract violation): stdout.r1.log (and stderr.r1.log if non-empty) sit next to stdout.log in the same per-turn directory. There is never an r2 — at most one retry per turn under any policy.
Used for moderator control flow / failures-md / debug, not persisted in transcript:
contract_ok — boolean. Convenience for the moderator: equivalent to error == null (any non-null error means contract validation either didn't run or didn't pass). Equivalently, contract_ok is true iff the moderator can use this turn's output without invoking the format fallback. Discard after deciding whether to apply the format fallback.stderr_path, retry_stderr_path — relative paths to .stderr files when they survived the empty-prune; null otherwise. The moderator already records stderr_tail on the transcript line for failed turns, so these paths are typically discarded; surface them only when manually debugging an error.duration_seconds — wall-clock seconds the subagent spent on this turn (sum across attempts). Aggregated into state.json.budget_remaining when applicable; not stored per-line in the transcript.
Forwarded to transcript line AND projected into the prompt-feed view:
context_delta — string or null. The verbatim bytes the subagent extracted from a context-delta fenced block (no [T<n>, <role>] prefix; null for an absent or whitespace-only block). Stored in transcript.jsonl.context_delta; projected into context.md per step 3.e.private_delta — string or null. Same shape; projected to agents/<cli>.md with [T<n>] prefix.
Parallel-turn ordering. When a phase declares parallel turns, the moderator dispatches all subagents concurrently and awaits all before committing any writes. After await, commit results to transcript.jsonl, context.md, and agents/<cli>.md in ascending turn_id order. All parallel subagents in a phase see the same pre-phase snapshot of context.md and agents/<cli>.md; they cannot observe each other's deltas. (This is intentional — parallel phases model independent reasoning. If a format needs deltas to be visible mid-phase, declare the turns sequential.)
Parallel + escalation. Even if one parallel subagent returns an auth error (or any other escalation-trigger per references/failures.md), the moderator still awaits the rest before acting — they are already running and cancelling them buys nothing. After await, commit every returned result in ascending turn_id order (including the auth error), then apply the escalation rule. For auth: stop dispatching new subagents anywhere, write state.json: aborted with the reason, hand back to senate. Do not treat sibling successes as invalid; they are part of the run record.
Commit pattern (mandatory). For each completed subagent result, the moderator's loop is: receive → write transcript line (atomic append, including the verbatim context_delta / private_delta strings) → project deltas into context.md / agents/<cli>.md → update state.json.last_activity_at (temp file + rename) → discard the result object. Do not retain text or parsed_output in your context after commit; reread transcript.jsonl if a later step needs them. The projection rule is canonical in ../senate/references/workspace.md § Invariants on derived projections.
Subagent crash / malformed return. A dispatched subagent may fail to return a structured result — tool failure, hard timeout outside the inner timeout wrapper, malformed JSON. In that case:
- Treat the missing turn as
error.kind = "unknown" and record it on the transcript line.
- Restore the log invariant before writing the transcript line: check whether
<turn-dir>/stdout.log exists (where <turn-dir> is stages/<n>-<name>/turns/<NNN>-<cli>-<role>/); if not, create it as an empty file (: > <path>) so the log_path invariant ("always resolves") still holds. Do the same for <turn-dir>/stdout.r1.log only if it exists partially or its presence is implied by what the subagent did before crashing — otherwise leave retry_log_path as null.
- Synthesize the transcript line:
text: "", exit_code: null, retry_count: 0, stderr_tail: "<reason the subagent gave, or 'subagent_crash'>", structured omitted, log_path set to the (now-guaranteed-existing) first-attempt path, retry_log_path per the rule above.
- Apply the format's fallback rule (same as any other terminal error).
- The escalation rules in
references/failures.md § Escalation still apply, with the synthetic unknown error counting toward unknown-error escalation thresholds. A subagent crash is never auth (auth would have been detected and returned by a working subagent), so do not abort the run on a single crash; rely on the existing escalation policy.
What the moderator owns (never delegate these to the subagent — they need the wider run state):
- Building the prompt (needs
context.md, agents/<cli>.md, transcript slice — the slice is curated; agents never see the raw transcript).
- Appending to
transcript.jsonl (sole writer; subagent never touches it).
- Projecting deltas into
context.md and agents/<cli>.md (sole writer; serialized in turn-id order).
- Atomic
state.json updates: last_activity_at at every turn boundary, full re-write at every stage boundary and checkpoint per ../senate/references/workspace.md.
- Failure escalation, re-plan callbacks, checkpoint decisions.
5. Adaptive moderation
The agenda is the plan, not a script. When reality diverges, decide whether to:
- Continue as planned — minor variance (one slow turn, one transient retry inside the subagent). Default. Note: contract re-prompts are owned by the per-turn subagent (§4a) and are invisible to this loop unless they fail twice.
- Apply format fallback — subagent returned
error.kind == "contract_violation" (the in-subagent re-prompt did not recover the reply) or another terminal error per references/failures.md. Per the format file's fallback rule.
- Pause for the user — checkpoint hit, or stage failed catastrophically (all agents refused, budget exhausted). Per
references/checkpoints.md.
- Call back to
debate-agenda for a re-plan — the situation has changed in a way the plan didn't anticipate (user changed direction, an agent kept refusing across stages, a checkpoint was rejected with a request for new structure). Pass: prior agenda, recent transcript slice, the reason. Receive: revised agenda. Resume at the next unfinished stage.
The bias should be toward continuing; only escalate when continuing would clearly produce a worse run.
Plan-validate-execute gate for destructive transitions
For any transition that mutates agenda.md, state.json, or already-written stage verdicts — specifically: roster swap mid-run, format swap, stage insertion or deletion, abort, resume-from-revise, or re-plan callback — do not mutate in place. Run this gate first:
- Plan. Write the intended mutation as a single self-describing block (e.g., diff of the agenda's
## Stages section, or the exact state.json field changes, plus a one-line reason).
- Validate. Check the plan against:
agenda-schema (every cli resolves to a playbook; every format resolves to a format file; every input_bindings references an earlier stage's output_bindings).- The
state.json schema in ../senate/references/workspace.md.
- Invariants: no rewriting of completed stages' verdicts; no breaking the append-only
transcript.jsonl; no skipping a required checkpoint.
- For a re-plan callback: the planner's revised agenda passes the same pre-flight checks as step 1 above.
- Execute. Apply the mutation. For agenda changes, the planner is the only writer of
agenda.md — call it back rather than editing the file yourself, and append a ## Revisions entry. For state.json, write atomically (temp file + rename). For abort, persist the abort reason in state.json before pausing.
If any validation step fails, do not execute. Surface to the user via senate with the plan and the failed check.
6. Stage completion
When a stage's termination condition fires (per the format file), the moderator:
- Runs the stage's synthesis turn — one designated role per the format (speaker / judge / editor / synthesizer). The synthesis turn's structured output and prose become the stage's verdict content.
- Writes the stage's verdict to
<run-dir>/stages/<index>-<name>/verdict.md. Every run has at least one stage (single-stage runs get stages/1-<format>/), so this is always a real path. The verdict's content is the synthesis turn's structured output and prose.
- Extracts
output_bindings and writes them to <run-dir>/bindings.json (cumulative across stages).
- Honors any checkpoint declared on this stage.
The moderator does not write the top-level <run-dir>/notes.md — that is meeting-note's job. The format-level "speaker writes the verdict" wording refers to the synthesis turn's content production; the moderator writes that content to stages/<N>-<name>/verdict.md (the bindings target), and the scribe folds it into notes.md after the run.
7. Hand off
When the last stage finishes:
- Update
<run-dir>/state.json: status: completed, completed_at: "...". Full schema in ../senate/references/workspace.md (## state.json schema).
- Return to
senate with a one-line summary and the path to the run dir.
senate then invokes meeting-note, which writes the user-facing notes.md (the merged file that replaces the old verdict.md + meeting-notes.md pair). The moderator never writes notes.md. The moderator does write per-stage stages/<n>-<name>/verdict.md files (the bindings target).
Single-stage vs multi-stage
There is one code path. A single-stage agenda walks one stage; a multi-stage agenda walks N. Bindings, checkpoints, and re-planning all work the same way.
Resume from pause
If the moderator is invoked on a run dir that already has transcript.jsonl content, follow the full resume / crash-recovery / revise / re-plan flows in references/checkpoints.md. The moderator owns state.json; the planner owns agenda.md. After the appropriate flow, continue from the first unfinished stage per the (possibly revised) agenda.
Files in this skill
SKILL.md — this file.references/context.md — context.md (shared scratchpad) and per-agent memory file conventions.references/contracts.md — structured-output contract discipline.references/failures.md — error taxonomy and retry policy.references/budget.md — wall-clock, token, and per-turn caps.references/checkpoints.md — human-in-the-loop pause / resume.
Related skills
../debate-agenda/ — produces the agenda.md this skill consumes; called back for mid-run re-plans. Format library at ../debate-agenda/formats/.../invoke-agent/ — per-CLI invocation playbooks, read inside the per-turn subagent for the CLI it is about to invoke.../meeting-note/ — runs after the moderator finishes; consolidates the transcript into user-facing notes.
