CLAUDE.md

@@ -16,7 +16,7 @@ The design lives in **`blueprint/project-family.md`**. Read it before any archit
 Load-bearing decisions from that document:
 
 - **Not upstreamable.** Nothing here needs to preserve Skald's schema or be portable back to it.
-- **Greenfield.** No users in production ⇒ **no migrations, no backwards compatibility**. Tables get restructured, renamed and moved freely; the schema collapses into a single clean baseline v1.
+- **~~Greenfield~~ — no longer true. The instance is in production.** There are live users with data we cannot recreate, so the greenfield licence (restructure, rename, wipe, recreate) has expired: **every schema change now needs a versioning mechanism**, and "drop the box and re-run setup" stopped being an acceptable answer. Until that mechanism exists, the only safe change is an additive one through `db::ensure_column` (see the DB section); anything that renames, drops, retypes or moves a column or table is **blocked** on building schema versioning first, not something to do carefully by hand. A user's `{userid}.db` is SQLCipher-encrypted and readable **only while they are logged in**, so a migration cannot be a boot-time sweep over every file — it has to run per user, at unlock, and be idempotent. Design for that when the time comes.
 - **Dual memory**: a private per-user pool plus a shared pool. A user's private space is encrypted so that nobody else — the admin included — can read it *through normal use of the system*. Never claim "mathematically impossible": the honest promise is transparency plus verifiability (§3).
 - **Threat model** (§2): the adversary is the **tempted admin**, who owns the box but does not recompile the binary or dump RAM. Do not design against a forensic attacker.
 - **Roles are data, not enums** (§0.1): a `roles` table binds permission-group, run-context and data-handling attributes. "Children" is a seeded preset row, never a hardcoded type.
@@ -132,7 +132,7 @@ The schema is split into two buckets (§5.1), and the split is the point:
 - **`create_registry_tables`** — instance-wide, readable without any user key: `users`, `roles`, `llm_providers`, `llm_models`, `transcribe_models`, `tts_models`, `image_generate_models`, `plugins`, `plugin_access` + `plugin_user_configs`, `approval_rules`, `tool_permission_groups`, `config`, `known_tools`, `llm_requests`, `mcp_catalog`, `mcp_global_servers` + `mcp_global_access`, `oauth_providers`, `role_capabilities`, `shared_folders` + `shared_folder_members`, `projects` + `project_members`, `supervision`, `system_agent_coverage`. The MCP tables back the Connectors model (§7/§14/§15 — see its own section); `oauth_providers` (accessor `db/oauth_providers.rs`) holds one row per identity provider (Google…) — endpoints + `client_id`/`client_secret` + `redirect_uri`, admin-owned household secrets (§4/§15b), never a per-user token. The last two pairs are junction-backed membership: `shared_folder_members` (accessor `db/shared_folders.rs`) for the on-disk shared folders (§6), `project_members` (accessor `db/project_members.rs`) for projects (see the Projects section) — both let a member be read-only (`can_write`) and both drive the container mount topology + the fs routing. Their FKs are registry→registry (same file), which is allowed — unlike an owner→registry key.
 - **`create_owner_tables`** — one owner's content, **identical schema in every file that has it**: `chat_sessions`, `chat_sessions_stack`, `chat_history`, `chat_llm_tools`, `chat_summaries`, `session_scratchpad`, `session_mcp_grants`, `stack_mcp_grants`, `scheduled_jobs`, `job_runs`, `system_agent_runs`, `system_agent_state`, `mcp_user_servers`, `mcp_events`, `sources`, `secrets`, `llm_request_payloads`, `memory_docs` (+ FTS5 `memory_docs_fts`), `reports`. `mcp_user_servers` (a user's activated per-user connectors) carries `catalog_name` as a **bare `TEXT` snapshot** of `mcp_catalog.name`, never a FK — an owner→registry key would fail every INSERT; for an OAuth connector it also snapshots `oauth_provider` + `deliver_json`, and its `api_key` column holds the refresh token (in the SQLCipher-encrypted file, so no column crypto). Because `memory_docs` is an owner table, one definition backs **private** memory in each `{userid}.db` and **shared** memory in `system.db` (the household owner) — see the memory namespace note below. (`projects`/`project_tickets` were owner tables in the single-user past: projects are shareable now, so `projects` + `project_members` are registry tables and `project_tickets` is gone.)
 
-Schema is greenfield (no migrations, §0), but a purely **additive** column lands on an existing DB in place: `db::ensure_column` runs `ALTER TABLE … ADD COLUMN` and swallows the "duplicate column" error, a no-op on a fresh DB where the `CREATE TABLE` already has the column. Used for the OAuth columns on `mcp_catalog` / `mcp_user_servers` so a dev box need not be wiped for an additive change (a full recreate is still valid).
+**The schema is no longer greenfield** (see the production note at the top): a full recreate is not an option anymore. `db::ensure_column` — `ALTER TABLE … ADD COLUMN` swallowing the "duplicate column" error, a no-op on a fresh DB where the `CREATE TABLE` already carries it — is therefore not a convenience for dev boxes anymore but the **only** change shape that is currently safe, and additive-with-a-default is the shape to design towards. Used for the OAuth columns on `mcp_catalog` / `mcp_user_servers`. Anything destructive waits for real versioning.
 
 **No foreign key in the owner bucket may point at a registry table.** SQLite cannot enforce a key across files, not even through `ATTACH`, and sqlx turns on `PRAGMA foreign_keys`: the `CREATE TABLE` succeeds and every `INSERT` fails. `db::tests::owner_tables_stand_alone_with_foreign_keys_on` enforces this by running the owner schema against a database holding nothing else, then inserting a row into each table. One key crossed and was fixed: `chat_history.model_db_id` (dropped — write-only, and `llm_requests.model_name` already records the model).
 

agents/assistant/AGENT.md

@@ -58,7 +58,7 @@ Rules of thumb:
 
 - **`mode=async`** — **the default for anything non-trivial.** It launches without blocking you, so you keep talking to the user while it runs. When it finishes, the system injects the result as a synthetic `task_completed` tool call — react to it and relay the outcome. After launching, tell the user it is running, then **do not poll** — the result arrives on its own.
 - **`mode=sync`** — run now and block for the answer. Only for **short** sub-tasks whose result you need immediately to finish composing your current reply.
-- **`mode=cron`** — schedule a recurring or one-shot task (7-field cron expression, `Europe/London`). The result arrives as a notification.
+- **`mode=cron`** — schedule a recurring or one-shot task (7-field cron expression; the tool description names the timezone it is evaluated in). The result arrives as a notification.
 
 ## Notifications
 

crates/skald-core/src/config.rs

@@ -39,13 +39,15 @@ pub struct LlmConfig {
 }
 
 /// Controls date/time injection in the dynamic tail of each LLM request.
+///
+/// The injected time is **always** truncated to the hour, and the block says so:
+/// see [`crate::loop_adapters::system`]. There is deliberately no rounding knob —
+/// the granularity is part of what the model is told, not an instance setting.
 #[derive(Debug, Clone, Deserialize)]
 pub struct DatetimeConfig {
     /// Inject the current date/time into the LLM context. Default: true.
     #[serde(default = "default_true")]
     pub enabled: bool,
-    /// When set, round the injected time down to the nearest N-minute boundary.
-    pub round_minutes: Option<u32>,
     /// IANA timezone name to use when formatting the injected timestamp.
     /// Populated at startup from the global `timezone` config field.
     #[serde(skip)]
@@ -54,7 +56,7 @@ pub struct DatetimeConfig {
 
 impl Default for DatetimeConfig {
     fn default() -> Self {
-        Self { enabled: true, round_minutes: None, timezone: None }
+        Self { enabled: true, timezone: None }
     }
 }
 

crates/skald-core/src/cron/mod.rs

@@ -57,6 +57,17 @@ impl TaskManager {
         })
     }
 
+    /// The zone cron expressions are evaluated in — the configured `timezone`,
+    /// else the system's. Exists so the `execute_task` tool description can name
+    /// it instead of hardcoding one: a model told the wrong zone writes a
+    /// correct-looking expression that fires at the wrong hour.
+    pub fn timezone_name(&self) -> String {
+        self.tz
+            .map(|tz| tz.name().to_string())
+            .or_else(|| iana_time_zone::get_timezone().ok())
+            .unwrap_or_else(|| "the server's local timezone".to_string())
+    }
+
     /// Called once after ChatSessionManager is built, breaking the circular dep.
     pub fn set_session(&self, session: Arc<ChatSessionManager>) {
         let _ = self.session.set(session);

crates/skald-core/src/loop_adapters/system.rs

@@ -143,6 +143,18 @@ fn os_description() -> &'static str {
     OS.get_or_init(|| os_info::get().to_string())
 }
 
+/// Formats an instant to hour precision: `Sunday 2026-08-02 17:00 +02:00`.
+///
+/// Minutes and seconds are dropped by the format string itself, so the
+/// truncation always happens in the zone being displayed. The weekday is part
+/// of the format on purpose — see [`AgentSystemContext::datetime_block`].
+fn render_hour<Tz: chrono::TimeZone>(dt: chrono::DateTime<Tz>) -> String
+where
+    Tz::Offset: std::fmt::Display,
+{
+    dt.format("%A %Y-%m-%d %H:00 %:z").to_string()
+}
+
 /// System IANA timezone name, computed once.
 fn system_timezone() -> Option<&'static str> {
     static TZ: std::sync::OnceLock<Option<String>> = std::sync::OnceLock::new();
@@ -169,23 +181,25 @@ impl AgentSystemContext {
 
     /// The current date/time + OS + cwd block (`None` when disabled).
     ///
-    /// Rounding exists for the prompt cache: a timestamp that changes every
-    /// second would invalidate any cached suffix, so the instance can quantize
-    /// it (this block is in the dynamic tail, after the cached prefix, but the
-    /// rounding still helps providers that cache further).
+    /// The time is **truncated to the hour**, always, and the block says so in
+    /// words. Two reasons, neither of which is the prompt cache — this block is
+    /// the last system message, after the whole conversation, so the cached
+    /// prefix is identical from one turn to the next whatever the timestamp says:
+    ///
+    /// 1. **Honesty.** A second-precision timestamp reads as exact to the model
+    ///    long after it stopped being true (it is built once per request, and a
+    ///    turn can run for minutes). An hour-precision one that announces itself
+    ///    as such lets the model know what it does *not* know — which matters
+    ///    when it is about to write a cron expression from "in ten minutes".
+    /// 2. It keeps the block cache-safe if it ever moves into the prefix.
+    ///
+    /// The weekday is spelled out: "next Tuesday" is a far more common ask than
+    /// the minute, and deriving it from a date is exactly the arithmetic models
+    /// get wrong.
     fn datetime_block(&self) -> Option<String> {
         if !self.datetime.enabled {
             return None;
         }
-        let secs = chrono::Utc::now().timestamp();
-        let secs = match self.datetime.round_minutes {
-            Some(m) if m > 0 => {
-                let bucket = (m as i64) * 60;
-                (secs / bucket) * bucket
-            }
-            _ => secs,
-        };
-
         let tz = self
             .datetime
             .timezone
@@ -193,30 +207,15 @@ impl AgentSystemContext {
             .and_then(|s| s.parse::<chrono_tz::Tz>().ok())
             .or_else(|| system_timezone().and_then(|s| s.parse::<chrono_tz::Tz>().ok()));
 
+        // Truncate in the *displayed* zone, not on the UTC epoch: a zone at a
+        // 30- or 45-minute offset (Asia/Kolkata, Asia/Kathmandu) would otherwise
+        // render as `17:30`, which is not an hour boundary and reads as precise.
         let (formatted, tz_name) = match tz {
-            Some(tz) => {
-                use chrono::TimeZone as _;
-                let f = tz
-                    .timestamp_opt(secs, 0)
-                    .single()
-                    .map(|dt| dt.format("%Y-%m-%dT%H:%M:%S%:z").to_string())
-                    .unwrap_or_else(|| {
-                        chrono::Local::now().format("%Y-%m-%dT%H:%M:%S%:z").to_string()
-                    });
-                (f, Some(tz.name().to_string()))
-            }
-            None => {
-                let f = chrono::DateTime::from_timestamp(secs, 0)
-                    .map(|utc| {
-                        utc.with_timezone(&chrono::Local)
-                            .format("%Y-%m-%dT%H:%M:%S%:z")
-                            .to_string()
-                    })
-                    .unwrap_or_else(|| {
-                        chrono::Local::now().format("%Y-%m-%dT%H:%M:%S%:z").to_string()
-                    });
-                (f, None)
-            }
+            Some(tz) => (
+                render_hour(chrono::Utc::now().with_timezone(&tz)),
+                Some(tz.name().to_string()),
+            ),
+            None => (render_hour(chrono::Local::now()), None),
         };
         let date_line = match tz_name {
             Some(name) => format!("Current date and time: {formatted} ({name})"),
@@ -227,7 +226,11 @@ impl AgentSystemContext {
         let cwd = "~";
 
         Some(format!(
-            "{date_line}\nOperating system: {}\nWorking directory: {cwd}\n\
+            "{date_line}\n\
+             The time above is truncated to the hour — you do not know the current minute. \
+             If you need it exactly (for instance to schedule something within the hour), \
+             run `date` with execute_cmd first.\n\
+             Operating system: {}\nWorking directory: {cwd}\n\
              Filesystem tools and execute_cmd resolve relative paths against your home directory.",
             os_description()
         ))
@@ -505,6 +508,23 @@ mod tests {
         assert_eq!(out, input);
     }
 
+    #[test]
+    fn hour_render_names_the_day_and_drops_the_minutes() {
+        let instant = chrono::DateTime::parse_from_rfc3339("2026-08-02T15:54:31Z").unwrap();
+        let rome = instant.with_timezone(&chrono_tz::Europe::Rome);
+        assert_eq!(render_hour(rome), "Sunday 2026-08-02 17:00 +02:00");
+    }
+
+    #[test]
+    fn hour_render_truncates_in_the_displayed_zone() {
+        // Asia/Kolkata is +05:30: truncating the UTC epoch instead would render
+        // 20:30 — an hour off AND not on an hour boundary, so it would read as
+        // a precise time. Truncation must happen after the zone conversion.
+        let instant = chrono::DateTime::parse_from_rfc3339("2026-08-02T15:54:31Z").unwrap();
+        let kolkata = instant.with_timezone(&chrono_tz::Asia::Kolkata);
+        assert_eq!(render_hour(kolkata), "Sunday 2026-08-02 21:00 +05:30");
+    }
+
     #[test]
     fn shared_folders_table_renders_access_and_description() {
         use crate::db::shared_folders::SharedFolderAccess;

crates/skald-core/src/loop_adapters/testkit.rs

@@ -181,7 +181,7 @@ pub fn mcp() -> Arc<dyn McpProvider> {
 /// The datetime block is disabled: it embeds `now()`, which no snapshot can
 /// pin down.
 pub fn datetime() -> DatetimeConfig {
-    DatetimeConfig { enabled: false, round_minutes: None, timezone: None }
+    DatetimeConfig { enabled: false, timezone: None }
 }
 
 /// The base tool definitions the projection is handed.

crates/skald-core/src/tools/cron_jobs.rs

@@ -18,18 +18,23 @@ use crate::tools::{SimpleExecution, Tool, ToolContext, ToolDescriptionLength, To
 pub struct ExecuteTask(pub Arc<TaskManager>);
 
 impl ExecuteTask {
-    fn description_text() -> &'static str {
-        "Create and run a task. Three modes:\n\
-         • mode=cron — scheduled by a 7-field cron expression (sec min hour dom month dow year, \
-           Europe/London timezone). Returns task_id and next scheduled run. Recurring unless the \
-           expression can only fire once.\n\
-         • mode=sync — run immediately, block until the agent finishes, and return the result inline. \
-           Best for short tasks (a few seconds to a few minutes).\n\
-         • mode=async — start the task in the background and return the task_id immediately. \
-           When the task completes its result will be delivered back to this chat automatically."
+    /// `tz` is the zone the scheduler actually evaluates expressions in
+    /// (`TaskManager::timezone_name`), never a literal: the description is what
+    /// the model reasons from, so a wrong zone here is an hours-off cron job.
+    fn description_text(tz: &str) -> String {
+        format!(
+            "Create and run a task. Three modes:\n\
+             • mode=cron — scheduled by a 7-field cron expression (sec min hour dom month dow year, \
+               {tz} timezone). Returns task_id and next scheduled run. Recurring unless the \
+               expression can only fire once.\n\
+             • mode=sync — run immediately, block until the agent finishes, and return the result inline. \
+               Best for short tasks (a few seconds to a few minutes).\n\
+             • mode=async — start the task in the background and return the task_id immediately. \
+               When the task completes its result will be delivered back to this chat automatically."
+        )
     }
 
-    fn schema() -> Value {
+    fn schema(tz: &str) -> Value {
         json!({
             "type": "object",
             "required": ["mode", "title", "prompt", "agent_id"],
@@ -41,7 +46,7 @@ impl ExecuteTask {
                 },
                 "title":       { "type": "string",  "description": "Short name for this task" },
                 "description": { "type": "string",  "description": "What this task does" },
-                "cron":        { "type": "string",  "description": "7-field cron expression — required when mode=cron (times in Europe/London). E.g. '0 0 9 * * * *' = every day at 09:00" },
+                "cron":        { "type": "string",  "description": format!("7-field cron expression — required when mode=cron (times in {tz}). E.g. '0 0 9 * * * *' = every day at 09:00") },
                 "prompt":      { "type": "string",  "description": "Prompt sent to the agent at each run" },
                 "agent_id":    { "type": "string",  "description": "Task agent to run (required; e.g. software-engineer, researcher, generalist). Must be a `task` agent — chat/system agents are rejected." }
             }
@@ -107,6 +112,7 @@ pub fn build_execute_task_interface_tool(
 ) -> crate::session::handler::InterfaceTool {
     use crate::session::handler::{InterfaceTool, ToolFuture};
 
+    let tz   = task_mgr.timezone_name();
     let tool = Arc::new(ExecuteTask(task_mgr));
 
     InterfaceTool {
@@ -114,8 +120,8 @@ pub fn build_execute_task_interface_tool(
             "type": "function",
             "function": {
                 "name": "execute_task",
-                "description": ExecuteTask::description_text(),
-                "parameters": ExecuteTask::schema(),
+                "description": ExecuteTask::description_text(&tz),
+                "parameters": ExecuteTask::schema(&tz),
             }
         }),
         handler: Arc::new(move |args: Value| -> ToolFuture {

default.config.yaml

@@ -60,9 +60,12 @@ llm:
   # execute_subtask) in a single response. Bounds fan-out to avoid provider
   # rate-limit storms. Omit for the default (4); set to 1 to force sequential.
   max_parallel_subagents: 4
+  # Injects "Current date and time: Sunday 2026-08-02 17:00 +02:00 (Europe/Rome)"
+  # as the last system message of each request. The time is always truncated to
+  # the hour and the block tells the model so, pointing it at `date` when it
+  # needs the exact minute — there is no rounding setting.
   datetime:
     enabled: true
-    round_minutes: 60  # Help with KV cache (instead of 10:54, it will pass 10:50 to the LLM)
 
   # ── Tool result size limit ──────────────────────────────────────────────────
   # When set, tool results from *previous* turns that exceed this character
@@ -109,11 +112,13 @@ llm:
   # ───────────────────────────────────────────────────────────────────────────
 
   # ── Date/time injection ─────────────────────────────────────────────────────
-  # Configured above as `datetime`. Rounding keeps the injected timestamp stable
-  # for up to N minutes, so the dynamic tail can be KV-cached across requests
-  # instead of changing every second.
+  # Configured above as `datetime`. The only setting is `enabled`.
+  # The injected time is always truncated to the hour: not for the prompt cache
+  # (the block is the LAST system message, so the cached prefix never changes
+  # whatever the timestamp says) but because a second-precision stamp reads as
+  # exact to the model long after it stopped being true. The block states the
+  # granularity and tells the agent to run `date` when it needs the minute.
   #   enabled: true          # set to false to disable injection entirely
-  #   round_minutes: 10      # round down to nearest N minutes (e.g. 10:56 → 10:50)
   # ───────────────────────────────────────────────────────────────────────────
 
   # ── LLM request/response log ────────────────────────────────────────────────