docs(roadmap): add #423 — diff json staged/unstaged are raw strings; no structured file-change objects

Adds ROADMAP #422 documenting the concrete export/resume no-session ErrorKind drift.

ROADMAP.md

@@ -6301,4 +6301,6 @@ Original filing (2026-04-18): the session emitted `SessionStart hook (completed)
 380. **Top-level `tokens --help --output-format json` hangs with zero stdout/stderr instead of returning bounded command help JSON** — dogfooded 2026-04-30 for the 02:30 nudge on current `origin/main` / rebuilt `./rust/target/debug/claw` with embedded `git_sha` `d95b230c`. After verifying #358 covered `cost --help`, a fresh adjacent probe on the token-budget surface showed the same silent failure class: repeated bounded runs of `timeout 8 ./rust/target/debug/claw tokens --help --output-format json` exited `124` with `stdout=0` and `stderr=0`. In the same rebuilt binary, `version --output-format json` returned promptly with version/build metadata, proving the binary itself and JSON output path are reachable. This is distinct from #358's cost help hang: the affected surface is the sibling `tokens` command help, which agents use before estimating prompt/session token budgets. **Required fix shape:** (a) make `tokens --help --output-format json` return static/bounded stdout JSON with `kind:"help"` or `kind:"tokens"`, `action:"help"`, usage, options, examples, supported output formats, and related slash/direct commands; (b) ensure help rendering does not initialize slow token accounting, session, or provider state; (c) if any dynamic provider is consulted, return a typed JSON timeout/unavailable error instead of hanging; (d) add regression coverage proving tokens help in JSON mode returns within a deterministic budget. **Why this matters:** token budgeting is a preflight clawability surface. If help hangs silently, automation cannot safely discover how to inspect or constrain token usage before running expensive prompts, and budget-aware wrappers stall at the discovery step. Source: gaebal-gajae dogfood follow-up for the 02:30 nudge on rebuilt `./rust/target/debug/claw` `d95b230c`.
 381. **Top-level `cache --help --output-format json` hangs with zero stdout/stderr instead of returning bounded command help JSON** — dogfooded 2026-04-30 for the 03:00 nudge on current `origin/main` / rebuilt `./rust/target/debug/claw` with embedded `git_sha` `d95b230c`. After #358 and #380 landed for the cost/tokens preflight help hangs, a fresh adjacent probe on the cache-control surface showed the same silent failure class: repeated bounded runs of `timeout --kill-after=1s 8s ./rust/target/debug/claw cache --help --output-format json` exited `124` with `stdout=0` and `stderr=0`. In the same rebuilt binary, `version --output-format json` returned promptly with version/build metadata, proving the binary itself and JSON output path are reachable. This is distinct from the separate `/cache` slash-command envelope mismatch class: the affected surface here is top-level `cache` command help, where agents need bounded local discovery before deciding whether to inspect, clear, or summarize cache state. **Required fix shape:** (a) make `cache --help --output-format json` return static/bounded stdout JSON with `kind:"help"` or `kind:"cache"`, `action:"help"`, usage, options, examples, supported output formats, and related slash/direct commands; (b) ensure help rendering does not initialize slow cache/session/provider state; (c) if any dynamic provider is consulted, return a typed JSON timeout/unavailable error instead of hanging; (d) add regression coverage proving cache help in JSON mode returns within a deterministic budget. **Why this matters:** cache inspection and cleanup are recovery/control-plane operations. If cache help hangs silently, claws cannot safely discover cache semantics before attempting cleanup, and automation stalls before it can choose a non-destructive cache action. Source: gaebal-gajae dogfood follow-up for the 03:00 nudge on rebuilt `./rust/target/debug/claw` `d95b230c`.
 
-409. **`init --output-format json` emits redundant parallel artifact schemas — `artifacts[].status` and flat `created[]`/`skipped[]`/`updated[]` arrays carry identical state, and `artifacts[].status:"skipped"` omits `skip_reason`** — dogfooded 2026-04-30 by Jobdori on `e939777f`. Running `claw init --output-format json` on a fresh directory returns a JSON object with two parallel representations of the same artifact set: (1) `artifacts: [{name, status}]` — a structured per-artifact array; and (2) `created: [...]`, `skipped: [...]`, `updated: [...]` — flat string arrays partitioned by status. Both encode the same four artifact names and their outcomes with no additional information between them. On a subsequent run in an already-initialized directory, every artifact has `status:"skipped"`, but no `reason` field is present on any artifact entry — automation cannot distinguish `"already_exists"` (safe to ignore) from `"permission_denied"`, `"dry_run"`, or `"conflicting_contents"` (each requiring a different response). The `message` field also embeds `"skipped (already exists)"` prose that is absent from the structured payload. **Required fix shape:** (a) pick one canonical artifact representation — either `artifacts[{name, status, reason?, path?}]` or the flat status arrays — and deprecate the other; (b) add a `skip_reason` or `reason` field to `artifacts[]` entries with `status:"skipped"` and `status:"error"`, using an enum such as `already_exists`, `permission_denied`, `dry_run`, `conflict`, `unknown`; (c) add optional `path` (absolute) to each artifact entry so automation can act on the real on-disk location without re-joining with `project_path`; (d) add regression coverage proving `init --output-format json` on an existing directory includes machine-classifiable skip reasons for every skipped artifact and does not rely on the prose `message` field for structured state. **Why this matters:** init is the bootstrapping surface automation uses to ensure a project is claw-ready. If skip classification requires parsing human prose and the structured payload has two redundant formats, claws either over-provision re-inits or cannot distinguish safe skips from blocked writes without brittle message scraping. Source: Jobdori live dogfood, `e939777f`, 2026-04-30.
+422. **`export --output-format json` and `--resume latest` report the same "no managed sessions" scenario using two different `kind` codes — `no_managed_sessions` vs `session_load_failed` — making "no session found" undetectable by a single kind-code check** — dogfooded 2026-04-30 KST (UTC+9) by Jobdori on `e939777f`. Running `claw export --output-format json` with no session present returns (on stderr, exit 1): `{"error":"no managed sessions found in .claw/sessions/<fingerprint>/","hint":"Start \`claw\` to create a session, then rerun with \`--resume latest\`.\nNote: claw partitions sessions per workspace fingerprint; sessions from other CWDs are invisible.","kind":"no_managed_sessions","type":"error"}`. Running `claw --resume latest /status --output-format json` with no session present returns (on stderr, exit 1): `{"error":"failed to restore session: no managed sessions found in .claw/sessions/<fingerprint>/","hint":"Start \`claw\` to create a session, then rerun with \`--resume latest\`.\nNote: claw partitions sessions per workspace fingerprint; sessions from other CWDs are invisible.","kind":"session_load_failed","type":"error"}`. Both describe the same root condition — there are no sessions to operate on — but they expose it via different `kind` discriminants. Automation that checks `kind == "no_managed_sessions"` to detect a cold workspace will miss the `--resume` path's `session_load_failed`, and vice versa. A wrapper that guards "run with --resume only if a session exists" must special-case both codes. The hint text is identical between them, suggesting the messages are logically equivalent. Additionally neither code matches the proposed canonical names `session_not_found` / `session_load_failed` as stable `ErrorKind` discriminants described in ROADMAP #77's fix shape, which explicitly proposes typed error-kind codes for session lifecycle failures. **Required fix shape:** (a) unify "no sessions found for this workspace fingerprint" under a single canonical `kind` code — either `no_managed_sessions` or `session_not_found` — used consistently by every command path that encounters an empty session registry; (b) if `session_load_failed` is a more general category (covering e.g. corrupt session files, IO errors, schema version mismatches), it should nest a concrete `reason:"no_managed_sessions"` or `reason:"session_not_found"` sub-field so callers can distinguish "empty registry" from "found but unreadable"; (c) align with the canonical error-kind contract proposed in #77; (d) add regression coverage proving `export` and `--resume latest` in an empty workspace both return an error with the same top-level `kind` code. **Why this matters:** session guard-rails in orchestration need a single stable `kind` to detect cold workspaces without enumerating all possible no-session synonyms. Two divergent codes for the same condition make defensive automation brittle and contradict the promise of machine-readable error envelopes. Source: Jobdori live dogfood, `e939777f`, 2026-04-30 KST (UTC+9).
+
+423. **`diff --output-format json` returns `staged` and `unstaged` as raw `git diff` prose strings, not structured file-change objects — automation must parse the diff text to identify which files changed** — dogfooded 2026-04-30 KST (UTC+9) by Jobdori on `e939777f`. Running `claw diff --output-format json` in a repo with unstaged changes returns `{"kind":"diff","result":"changes","staged":"","unstaged":"diff --git a/ROADMAP.md b/ROADMAP.md\nindex ca63e33..2e4b74e 100644\n--- a/ROADMAP.md\n+++ b/ROADMAP.md\n@@ -1,3 +1,4 @@\n+// test change\n ..."}`. The `staged` and `unstaged` fields are raw multi-line `git diff` output strings. A claw that wants to know which files changed, how many lines were added/removed, or whether a specific path is in the diff must parse the raw unified diff format — there are no structured `files:[{path, additions, deletions, status}]` fields, no `changed_files_count`, no per-file change summary. The `result` field (`"changes"`, `"clean"`, `"no_git_repo"`) is machine-readable, but everything else is raw prose. Automation that relies on `diff --output-format json` to make decisions (e.g. "did the test files change?", "are there staged changes before a commit?") must implement a full unified diff parser. **Required fix shape:** (a) add a `files` field containing structured per-file change metadata: `{path, status:"added"|"modified"|"deleted"|"renamed", additions:int, deletions:int, old_path:null|string}`; (b) add top-level `total_additions:int` and `total_deletions:int` summary fields; (c) keep `staged` and `unstaged` raw strings as optional verbatim fields (e.g. under `raw_staged`, `raw_unstaged`) for callers that need the full text; (d) add regression coverage proving `diff --output-format json` in a workspace with changes includes a `files[]` array with at least one entry containing `path` and `status` fields. **Why this matters:** diff inspection is a key control-plane signal for claws deciding whether to commit, what to commit, or whether user-edited files need re-analysis. If the only machine-readable diff signal is a raw unified diff string, every orchestration layer must bundle a full diff parser, re-deriving what `git diff --stat` would have given for free. Source: Jobdori live dogfood, `e939777f`, 2026-04-30 KST (UTC+9).