echo-memory — v0.7

Persistent memory for Claude / CoWork sessions via the ECHO Obsidian vault, driven over the Obsidian Local REST API. No MCP server — the skill makes direct REST calls, now through a bundled validated client (scripts/echo.sh).

Built for Jason Stedwell (Director of Technical Services / Systems Engineer, MPM / ALABAMA wISP), who is both the operator and the architect of this vault. This is a personal plugin, not for distribution.

This repository (jason/echo-v.05) holds the plugin source (tracked tree at echo-memory.plugin.src/), the built echo-memory.plugin package artifact (rebuilt on each version bump), and a credential-free A/B eval/ harness.

0.7 in one line: the prose-and-raw-curl skill grew an executable spine — a status-checking API client, a machine-readable routing manifest the linter enforces, deterministic bootstrap/migrate scripts, an advisory multi-writer lock, four slash commands, and an eval harness. See the 0.7.0 version-history entry for the full list.

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Core design principle — the plugin is the single source of truth

Everything that defines how ECHO behaves — bootstrap/repair logic, the operating contract, the taxonomy, frontmatter conventions, the routing map, and the canonical note templates — ships inside the plugin under skills/echo-memory/.

The vault itself holds data only. There are no CLAUDE.md / BOOTSTRAP.md / STRUCTURE.md / index.md control docs in it. The single in-vault control artifact is a one-line marker, _agent/echo-vault.md, that records the schema version.

Three consequences follow:

• Self-bootstrapping — point the REST API at an empty Obsidian vault and the plugin stands up the full folder tree, templates, anchors, and marker from its bundled scaffold/.
• Easy to update — change behavior by updating the plugin, not by editing files scattered through the vault.
• Portable — the same plugin brings any empty vault online identically; nothing essential depends on files pre-existing in the vault.

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Configuration

The plugin is hardcoded for a single personal endpoint:

• Server: https://echoapi.alwisp.com (reverse proxy → backend Obsidian Local REST API). This is the only valid endpoint — never use LAN addresses (10.x, 192.168.x, :27124); those belong to retired memory systems. Override per-run with ECHO_BASE.
• Auth: a bearer token stored in the skill / references and injected by scripts/echo.sh. The key lives only in the plugin — never inside a vault note (per the vault's own safety rules). Override with ECHO_KEY.
• TLS: the endpoint presents a valid certificate, so -k is not needed.

Vault paths are addressed at the root (e.g. GET /vault/_agent/context/current-context.md). Prefer scripts/echo.sh over raw curl: it injects auth, checks HTTP status (a failed write exits non-zero instead of looking like success), retries transient 5xx, verifies PUTs, and does idempotent appends.

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Requirements

• Obsidian running on the backend with the Local REST API plugin enabled.
• HTTPS reachability to https://echoapi.alwisp.com from the Claude / CoWork session environment.

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Repository layout

echo-v.05/
├── echo-memory.plugin              ← built, installable plugin (zip artifact, rebuilt on version bump)
├── echo-memory-<version>.plugin    ← versioned build artifacts (history)
├── eval/                           ← credential-free A/B eval harness (0.6 vs 0.7); not bundled
│   ├── mock_olrapi.py              ← deterministic mock of the REST API + fault injection
│   ├── run_eval.py                 ← orchestrator (runs the real echo.sh vs modeled raw curl)
│   └── README.md
└── echo-memory.plugin.src/         ← tracked source tree (the plugin)
    ├── .claude-plugin/plugin.json  ← manifest (name, version, description)
    ├── README.md                   ← plugin-level README
    ├── commands/                   ← slash commands: echo-load, echo-save, echo-triage, echo-health
    └── skills/echo-memory/
        ├── SKILL.md                ← operating procedure (authoritative)
        ├── references/
        │   ├── operating-contract.md   ← durable principles + safety rules + concurrency
        │   ├── bootstrap.md            ← bootstrap / repair / migrate manifest
        │   ├── vault-layout.md         ← canonical layout + frontmatter conventions
        │   ├── routing-map.md          ← complete endpoint→logic routing map (human authority)
        │   ├── api-reference.md        ← REST endpoint patterns + routing map
        │   └── session-log-template.md
        ├── scripts/                    ← executable logic (NEW in 0.7)
        │   ├── echo.sh                 ← validated API client (auth, status-check, retry, verify, lock)
        │   ├── routing.json            ← canonical machine-readable route manifest (linter enforces it)
        │   ├── vault-lint.sh           ← read-only invariant checker (Vault Health)
        │   ├── bootstrap.sh            ← deterministic, idempotent vault setup/repair
        │   └── migrate.sh              ← deterministic schema migration (dry-run by default)
        └── scaffold/                   ← verbatim files the bootstrap writes into the vault
            ├── echo-vault.md           ← bootstrap marker
            ├── README.vault.md         ← thin human signpost
            ├── anchors/                ← operator-preferences, current-context, inbox seeds
            └── templates/              ← 8 canonical note templates

Division of responsibility: SKILL.md owns day-to-day procedure (loading order, search-first, triage, scope switching, PATCH rules) and points at the bundled tooling. references/operating-contract.md owns the durable, client-independent principles, safety rules, and concurrency model. scripts/routing.json is the machine-readable source of truth for routing; references/routing-map.md is its human-readable authority. The other references are the canonical layout, API, and bootstrap specs.

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Bundled tooling (0.7)

Executable logic ships under skills/echo-memory/scripts/; the agent prefers it over hand-built curl.

Tool	Purpose
echo.sh	The validated API client. get/ls/map/search/put/post/append/patch/fm/bump/delete/lock/unlock. Injects auth, checks HTTP status (non-zero exit on ≥400 — a failed write can't masquerade as success), one bounded retry on transient 5xx/connection errors, read-back verify on PUT, idempotent append (read-before-POST), correct :: heading targets.
routing.json	The canonical machine-readable route manifest — one regex pattern per valid destination plus retired paths. The single source of truth for "what may be written where"; vault-lint.sh enforces it.
vault-lint.sh	Read-only invariant checker (Vault Health). Real YAML parsing, clock injected via ECHO_TODAY, exits 3 if the vault isn't bootstrapped (instead of falsely reporting "clean").
bootstrap.sh	Deterministic, idempotent, probe-before-write vault setup/repair (--dry-run to preview). Resolves the scaffold relative to itself, so it works from any CWD.
migrate.sh	Deterministic schema migration. Dry-run by default; destructive steps gated behind --apply and printed first.

Slash commands

/echo-load (cold-start read), /echo-save <text> (route + persist), /echo-triage (drain the inbox), /echo-health (run the linter) — explicit, reproducible entry points to the procedures below.

Concurrency (shared vault)

ECHO is read/written by multiple clients (Claude Code and CoWork). Single-line files (heartbeat/last-session.md, current-context.md::Scope) and append targets (inbox.md, ## Agent Log) assume one writer at a time. Before an overlapping burst of writes, take the cooperative advisory lock (echo.sh lock <id> → _agent/locks/vault.lock, TTL-reclaimable) and release it at session end. Idempotent append and status-checked writes are the second line of defense.

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Vault layout (data only, root-addressed)

/vault/
├── README.md          ← thin human signpost (NOT read for routing)
├── inbox/
│   ├── captures/      ← quick captures (inbox.md), date-prefixed lines
│   ├── imports/       ← raw imported material
│   └── processing-log/
├── journal/          ← one append-only time-series stream; rollups are coarser journal entries (no separate reviews/ tree)
│   ├── daily/         ← YYYY-MM-DD.md (has an "## Agent Log" section)
│   ├── weekly/        ← YYYY-Www.md (ISO week, opt-in rollup)
│   ├── monthly/       ← YYYY-MM.md (monthly rollup)
│   ├── quarterly/     ← YYYY-Qn.md (manual / on request)
│   ├── annual/        ← YYYY.md (manual / on request)
│   └── templates/
├── projects/          ← lifecycle: incubating → active → on-hold / archived
│   ├── active/  incubating/  on-hold/  archived/
│   └── project-template.md
├── areas/             ← business / personal / learning / systems
├── resources/
│   ├── companies/     ← <slug>.md — organizations (clients, vendors, partners, employers)
│   ├── concepts/  references/  meetings/
│   └── people/        ← <name>.md
├── decisions/
│   ├── by-date/       ← YYYY-MM-DD-<slug>.md (ADR-style) — the canonical home
│   └── decision-template.md   (by-project/ is retired, not created)
│  (reviews/ is retired — journal rollups live under journal/; vault-health under _agent/health/)
└── _agent/
    ├── echo-vault.md  ← bootstrap marker: schema_version + date (plugin-owned probe)
    ├── context/       ← current-context.md and task bundles
    ├── memory/
    │   ├── working/   ← transient, time-boxed
    │   ├── episodic/  ← what happened, when
    │   └── semantic/  ← durable facts / patterns (operator-preferences.md)
    ├── sessions/      ← YYYY-MM-DD-HHMM-<slug>.md
    ├── health/        ← YYYY-MM-vault-health.md (monthly self-maintenance audit)
    ├── templates/     ← canonical note templates (seeded from the plugin's scaffold/)
    ├── skills/        ← active / archived capability catalog
    ├── heartbeat/     ← last-session.md pointer (read at load, written at session end)
    └── locks/         ← vault.lock — cooperative advisory multi-writer lock (echo.sh lock/unlock)

Memory model

Layer	Path	What it holds
Working	_agent/memory/working/	Transient, time-boxed state
Episodic	_agent/memory/episodic/	What happened, when
Semantic	_agent/memory/semantic/	Durable facts, patterns, preferences (operator-preferences.md)
Context	_agent/context/	Task-focused reading lists + active scope

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Operating procedures (logic)

Cold-start loading

Load memory at the start of any substantive conversation (anything beyond a single quick factual question). The cold-start reads are issued in parallel (one batch of 5–6 GETs):

1. _agent/echo-vault.md — the bootstrap marker. 404 → vault not set up (run bootstrap); 200 → check schema_version and migrate if older than the plugin's.
2. _agent/memory/semantic/operator-preferences.md — Jason's profile.
3. _agent/context/current-context.md — active scope + Scope History.
4. _agent/heartbeat/last-session.md then _agent/sessions/ — read the heartbeat pointer first (O(1) jump to the latest log); fall back to the listing's ~5 most recent by reverse lexical sort.
5. journal/daily/YYYY-MM-DD.md — today's note (404 is fine).
6. inbox/captures/inbox.md — inbox-depth probe for the load-time reconcile.

After the batch, reconcile: if the inbox holds captures older than ~7 days, surface the count and offer to triage (so triage self-fires rather than waiting to be invoked); and if the active scope diverges from what Jason just asked for, run Scope Switching.

If a specific project is in play, follow up with a search/simple/ across all lifecycle subfolders, querying both the slug and any human title used in conversation, then read the match at projects/<lifecycle>/<slug>.md. Loading is not narrated to the operator.

Inbox triage

inbox/captures/inbox.md is the catch-all. At session start, GET it; if it holds lines older than ~7 days that were never routed, surface a count once and offer to triage. Accepted items route to their proper home (preference → operator-preferences; project idea → projects/incubating/; durable fact → semantic; person fact → resources/people/), with the move recorded one-line in inbox/processing-log/YYYY-MM-DD.md as an audit trail. Originals aren't deleted unless explicitly asked.

Project lifecycle

Projects move through four folders; the folder name and the status: frontmatter field MUST agree — they are two views of one state. A file in projects/active/ with status: on-hold is broken state.

Folder	status:	Meaning
incubating/	incubating	Idea captured; not actively worked
active/	active	Current work (default for anything in motion)
on-hold/	on-hold	Paused but still tracked; resumable
archived/	archived	Done, abandoned, or rolled up — not deleted

Promotion = move the file and update status: in the same change.

Scope switching

_agent/context/current-context.md tracks one active scope. When scope changes: (1) PATCH-prepend a dated bullet capturing the prior scope to ## Scope History; (2) PATCH-replace ## Scope with the new scope; (3) bump the frontmatter updated:. Scope History is trimmed to the last ~10 entries.

Daily note — Agent Log

After substantive activity, append a one-line entry to today's daily note's ## Agent Log. The procedure is resilient: GET the note → if 404, PUT it from the template → if 200 but the heading is missing, POST the heading. Heading detection greps the raw markdown for an anchored ^## Agent Log — not the document-map JSON, whose headings are ::-delimited paths (a bug fixed in 0.4.1 that previously appended duplicate headings).

Session logging

At the end of substantive conversations (those producing decisions, artifacts, or commitments), write a session log to _agent/sessions/YYYY-MM-DD-HHMM-<slug>.md. The four-digit HHMM component is canonical, not optional — it makes filenames lex-sort in true chronological order, which cold-start loading depends on. New writes are validated against ^\d{4}-\d{2}-\d{2}-\d{4}-[a-z0-9-]+\.md$.

Journal rollups

The journal is one append-only time-series stream; rollups are coarser-grained entries on the same timeline, so they live under journal/ — there is no separate reviews/ tree.

• Weekly — opt-in; offered on the first substantive session of a new ISO week, written only if accepted, to journal/weekly/YYYY-Www.md.
• Monthly — offered alongside the Vault Health pass on the first session of a calendar month, to journal/monthly/YYYY-MM.md.
• Quarterly / annual — manual / on request only, to journal/quarterly/YYYY-Qn.md and journal/annual/YYYY.md.

Vault Health (monthly)

Agent self-maintenance (not a journal entry), written to _agent/health/YYYY-MM-vault-health.md. Run scripts/vault-lint.sh (or /echo-health) with ECHO_TODAY = the conversation's date so stale/aging math uses one clock. It mechanically asserts: folder↔status mismatch, duplicate slugs across lifecycle folders, wikilinks in frontmatter (swept across all folders), duplicate ## Agent Log headings, stale active projects (updated: > 30 days), aging inbox items (> 14 days), paths matching no route in routing.json or sitting at a retired path, and frontmatter integrity (missing required fields, updated < created, future dates, wikilinks leaking into source_notes). Exit codes: 0 clean · 1 violations · 2 unreachable · 3 not bootstrapped. Findings are reported, not auto-fixed.

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Write-safety rules

• Search first (mandatory for new notes). Before creating any slug-addressed note, POST /search/simple/?query=<slug> across the whole vault (and search the human title too) — listing one folder misses duplicates elsewhere. On a match: promote/merge from a non-active subfolder, update-in-place in the same folder, or ask which is canonical if elsewhere.
• Read before append (idempotency). POST is not idempotent — a retry duplicates lines. Before any POST that adds an entry (inbox, Agent Log, an Observations/Log heading), GET the target and skip if the exact line is already present. (Does not apply to PUT or PATCH-replace.)
• Bump updated: on substance. PATCH the frontmatter updated: to today after a meaningful content change (status update, decision, scope switch). Skip it for routine log appends — bump on substance, not heartbeat.
• Preserve created:. It is the earliest known date the entity was tracked anywhere — never reset it to "today" when merging.
• No [[wikilinks]] in frontmatter — YAML parses them as nested lists and they break. Cross-references go in a ## Related body section. source_notes holds plain relative-path strings (backward links to inputs only).
• Check the HTTP status (or use echo.sh). A PATCH to a missing heading returns 400 invalid-target (40080) and the write is silently lost; a transient 503 or an accepted-but-unpersisted PUT can do the same. echo.sh enforces this (exit ≠ 0, retry, read-back verify); raw curl must branch on -w "%{http_code}". Treat ≥ 400 as a failed op — surface it, don't continue.

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REST API operations

Server https://echoapi.alwisp.com, bearer auth, root-addressed paths.

Operation	Method	Notes
Read file	GET /vault/<path>	Raw markdown; 404 = absent
Read heading	GET /vault/<path>/heading/<H1>::<H2>	::-delimited, URL-encode spaces as %20
List dir	GET /vault/<dir>/	Trailing slash; returns {files, folders}
Document map	GET + Accept: application/vnd.olrapi.document-map+json	Discover exact heading / block / frontmatter targets
Append	POST /vault/<path>	Appends to end-of-file; creates if absent
Create / overwrite	PUT /vault/<path>	Auto-creates intermediate directories
Patch section	PATCH /vault/<path>	Operation: append|prepend|replace, Target-Type: heading|frontmatter|block
Search	POST /search/simple/?query=<terms>	Returns [{filename, score, matches}]
Delete	DELETE /vault/<path>	Only on explicit operator request

PATCH heading targets must be the full ::-delimited path from the top-level heading (e.g. Operator Preferences::Fact / Pattern) — a bare subheading name returns 400 invalid-target (errorCode 40080). GET the document map first when unsure of the exact path, and copy the heading string verbatim.

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Memory routing map

Situation	Vault path	Method
Quick capture / unsorted	inbox/captures/inbox.md (date-prefixed line)	POST
Raw imported material	inbox/imports/	PUT
Operator preference / durable fact	_agent/memory/semantic/operator-preferences.md	PATCH
Other durable facts, patterns	_agent/memory/semantic/<slug>.md	PUT
Event record (what happened)	_agent/memory/episodic/<slug>.md	PUT
Short-lived, time-boxed state	_agent/memory/working/<slug>.md	PUT
Task-scoped context / focus	_agent/context/current-context.md	PATCH / PUT
Working-session log	_agent/sessions/YYYY-MM-DD-HHMM-<slug>.md	PUT
Long-running project state	projects/<lifecycle>/<slug>.md (folder and status: MUST agree)	PUT + PATCH
Standing area of responsibility (no end state)	areas/<domain>/<slug>.md (business/personal/learning/systems)	PUT
Non-obvious decision (ADR)	decisions/by-date/YYYY-MM-DD-<slug>.md (mirror into a project's ## Key Decisions; else skip)	PUT
Person context	resources/people/<name>.md	PUT / PATCH
Concept / reference note	resources/concepts/ or resources/references/	PUT
Meeting notes / call recap	resources/meetings/YYYY-MM-DD-<slug>.md	PUT
Skill / plugin capability entry	_agent/skills/active/<slug>.md (→ archived/ when retired)	PUT
Daily activity / Agent Log	journal/daily/YYYY-MM-DD.md	POST / PATCH
Journal rollup	journal/{weekly/YYYY-Www,monthly/YYYY-MM,quarterly/YYYY-Qn,annual/YYYY}.md	PUT
Vault-health audit (agent self-maintenance)	_agent/health/YYYY-MM-vault-health.md	PUT
Session-end orientation pointer	_agent/heartbeat/last-session.md	PUT
Bootstrap marker (plugin-owned)	_agent/echo-vault.md (schema_version, date)	GET / PUT

The complete endpoint→logic map — every path with its trigger and why it's distinct — is skills/echo-memory/references/routing-map.md.

Slug rules: kebab-case, ASCII, ~40 chars max. Every file carries canonical YAML frontmatter.

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Frontmatter conventions

Every note opens with this block (fill what applies; leave the rest empty rather than guessing):

---
type:            # daily-note | project | area | concept | reference | person |
                 # meeting | decision | review | session-log | working-memory |
                 # episodic-memory | semantic-memory | context-bundle | skill | ...
status:          # active | draft | done | archived | complete | incubating | on-hold
created:         # YYYY-MM-DD — earliest known date the entity was tracked
updated:         # YYYY-MM-DD — bumped on meaningful change
tags: []
agent_written:   # true on agent-generated notes
source_notes: [] # plain relative paths (backward links) — NEVER [[wikilinks]]
---

agent_written: true + a populated source_notes is the key signal separating agent-managed content from human-authored content.

operator-preferences.md — Rules vs Observations

• ## Fact / Pattern — promoted, deduped, timeless rules (no date prefix).
• ## Observations — timestamped raw observations (- 2026-06-06: ...); the default landing zone for new evidence.

Observations are promoted into Fact / Pattern (dropping the date) once a pattern stabilizes, and trimmed to the last ~30 entries.

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Bootstrap, repair & migration

The plugin carries everything needed to stand up a vault in scaffold/; there is no dependency on any in-vault control doc. In 0.7 these are scripts (scripts/bootstrap.sh, scripts/migrate.sh), not hand-run curl loops — the prose in references/bootstrap.md documents what they do and serves as the fallback.

• Probe — GET _agent/echo-vault.md. 200 → bootstrapped (check schema_version); 404 → run a fresh bootstrap.
• Fresh bootstrap (bootstrap.sh; idempotent, additive — never overwrites): create the folder tree (a one-line README seeds each leaf since Obsidian/git ignore empty dirs) → PUT the 8 templates to their mirrored vault paths → PUT the 3 anchor seeds only if absent (the operator-preferences seed is deliberately empty — no fabricated facts) → PUT the thin vault README → PUT the marker last (so the vault is only flagged "set up" once everything is in place) → write a first-run trace (daily note + session log). --dry-run previews.
• Repair — bootstrap.sh again: GET-probes each path and creates only what's missing; malformed files are flagged, never replaced.
• Migrations — migrate.sh reads the marker's schema_version, applies each intervening migration (dry-run by default; --apply to perform moves/deletes), and stamps the marker. 0 → 1 removed the old in-vault control docs (CLAUDE.md / BOOTSTRAP.md / STRUCTURE.md / index.md); 1 → 2 folded reviews/ into journal/ + _agent/health/.

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Skill triggers

Skill	Triggers
echo-memory	"remember that", "save to memory", "what do you know about me", "load my profile", "check my notes", "log this decision", "add to my inbox" — and proactively at the start of substantive conversations

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Safety rules (operating contract)

• Do not fabricate facts, relationships, or prior decisions.
• Do not mass-restructure the vault unless explicitly asked.
• Do not delete notes unless deletion is explicitly requested and clearly safe.
• Never store secrets or API keys inside a vault note.
• Default to additive updates and explicit status changes over destructive edits.
• Write in third person about Jason ("Jason prefers X"). Do not cross-write with other vaults (Bryan's goldbrain is separate).

If the API returns a connection error, timeout, or 502 (usually Obsidian / the REST plugin not running), tell Jason once that the vault is unreachable and proceed without memory — don't retry repeatedly.

---

Version history

Version	Highlights
0.3.0	Source promoted from zip-only to a tracked tree (echo-memory.plugin.src/); .plugin becomes a build artifact. All 7 skill-improvement items applied: search-first before writes, resilient daily Agent Log, created: semantics, project lifecycle + folder↔status rule, canonical HHMM session filenames, read-most-recent-N sessions, source_notes defined as backward links.
0.4.0	Efficiency + robustness pass: parallel cold-start loading, idempotent POST (read-before-append), doc-map-before-first-PATCH, scoped updated: bump, Inbox Triage, Scope Switching, monthly Vault Health, Rules-vs-Observations split, formal deprecation of decisions/by-project/, heartbeat pointer.
0.4.1	Bugfix: daily-note Agent Log heading detection now greps raw markdown for ^## Agent Log instead of the ::-delimited doc-map JSON (which never matched and appended duplicate headings). Added Scope Switching cold-start test harness.
0.5.0	Self-bootstrap + control-logic-in-plugin. Plugin becomes the single source of truth: bundled scaffold/ (8 templates, 3 anchor seeds, thin vault README, marker) bootstraps an empty vault with no external/local-path dependency. New operating-contract.md (principles + safety from the old in-vault CLAUDE.md); bootstrap.md rewritten as a portable bootstrap/repair/migrate manifest. Cold-start probe moved from /vault/BOOTSTRAP.md to _agent/echo-vault.md (carries schema_version). Live vault migrated to data-only.
0.5.1	Routing-doc consistency pass: decision-mirror heading unified to ## Key Decisions; stale Current status PATCH examples corrected to Status; vault-layout inline project example refreshed to the real template. All 17 projects/active/ notes normalized losslessly to the canonical template heading set; android-mqtt-shell moved to incubating/ (was broken status: upcoming in active). Plugin repackaged (21 files).
0.6.0	Schema 2. #8 Inbox auto-fire: the Loading procedure adds an inbox-depth GET and a load-time Reconcile step (inbox triage + scope-drift), so triage self-fires. #10 Routing: reviews/ retired — weekly/monthly/quarterly/annual rollups fold into journal/{weekly,monthly,quarterly,annual}/, vault-health moves to _agent/health/; new references/routing-map.md is the complete audited endpoint→logic map. Recs: heartbeat pointer operationalized (read first at load, written at session end); new scripts/vault-lint.sh mechanically checks vault invariants. Dead refs pruned (archive/, _agent/outputs/, resources/source-material). Migration 1 → 2 in bootstrap.md.
0.7.0	Schema 2 (unchanged layout). Hardening pass — gave the prose-and-curl skill an executable spine. S2 scripts/echo.sh: one validated client wrapping every verb with auth, HTTP-status checking (failed writes exit non-zero instead of looking like success), one bounded retry on 5xx, read-back-verified PUT, and idempotent append. S3 scripts/routing.json: canonical machine-readable route manifest; vault-lint.sh enforces it (flags unknown/retired paths). S4 deterministic scripts/bootstrap.sh + scripts/migrate.sh (idempotent, dry-run, probe-before-write; fixes the old CWD-relative @scaffold/... empty-body bug). S5 cooperative advisory lock (_agent/locks/vault.lock) + documented multi-writer model. M1/M2/M5 linter rewrite: real YAML parsing, injected clock (ECHO_TODAY), exits 3 (not "clean") on an un-bootstrapped vault, plus routing-membership + frontmatter-integrity checks. M3 status-check guidance throughout. M4 four slash commands (/echo-load, /echo-save, /echo-triage, /echo-health). Added a credential-free A/B eval/ harness (mock REST API + fault injection): isolates a −76% generated-token I/O layer and 4 → 0 silent write failures vs 0.6.