Projects: classes as entities, and the sidebar fits short windows

A project is a class with facts (description, status, kind, party,
dates, links, notes) in one project.set event behind the format
feature projects. Four tools (books.add_project, update_project,
projects, project); documents and decisions link to projects; B-37:
on-spec costs are expensed as incurred, repayment is revenue, and the
unrecovered cost is never below zero (Kani). Viewer: a Projects list
and a project page with its figures, by month and by account. The
sidebar measures its footer instead of reserving a fixed 172 px.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01T3gXMVt7XJPi6ens1or9Dj

crates/ledger-mcp/tests/hostile_args.rs

@@ -1366,6 +1366,7 @@ fn reads_of_old_books() -> Vec<(&'static str, Value)> {
         ("books.list_receipts", json!({})),
         ("books.list_vendors", json!({})),
         ("books.list_classes", json!({})),
+        ("books.projects", json!({})),
         ("books.parties", json!({})),
         ("books.statements", json!({})),
         ("books.reconciliations", json!({})),
@@ -1715,3 +1716,20 @@ fn hostile_renames_ranges_and_categories_are_answered() {
     );
     reopens(m, &p, "P3's hostile inputs");
 }
+
+/// books.project over the whole calendar answers, its months the last 240
+/// (each month is a statement: a hundred thousand of them would not).
+#[test]
+fn a_project_over_the_whole_calendar_answers_quickly() {
+    let p = places("project-wide");
+    let mut m = Mcp::start(&p);
+    fixture(&mut m, &p);
+    m.ok("books.add_project", json!({"name": "Harbor"}));
+    let t = std::time::Instant::now();
+    let p = m.ok(
+        "books.project",
+        json!({"project": "Harbor", "start": "0001-01-01", "end": "9999-12-31"}),
+    );
+    assert_eq!(p["period"]["by_month"].as_array().unwrap().len(), 240);
+    assert!(t.elapsed() < std::time::Duration::from_secs(30));
+}

crates/ledger-mcp/tests/mcp_stdio.rs

@@ -178,7 +178,7 @@ fn mcp_end_to_end_over_stdio() {
     // Tool listing: the narrow tools; chart is read-only.
     let list = mcp.request("tools/list", json!({}));
     let tools = list["result"]["tools"].as_array().unwrap();
-    assert_eq!(tools.len(), 112, "expected 112 tools, got {}", tools.len());
+    assert_eq!(tools.len(), 116, "expected 116 tools, got {}", tools.len());
     // Files come in as tool input: books.begin_upload, never a local path.
     assert!(tools.iter().any(|t| t["name"] == "books.begin_upload"));
     assert!(!tools.iter().any(|t| t["name"] == "books.import_local_file"));

crates/ledger-mcp/tests/oracle_mcp.rs

@@ -3259,6 +3259,16 @@ fn references_resolve_unless_truly_ambiguous() {
     let dir = test_dir("refs");
     let s = Store::create(&data_dir(&dir), Currency::USD).unwrap();
     drop(s);
+    // Classes as an earlier version could write them (a name of digits
+    // only can't be added now): 1 "placeholder-name", 2 named "1", 3
+    // named "3".
+    let mut w = ledger_store::JournalWriter::open(&data_dir(&dir).join(ledger_store::JOURNAL_FILE))
+        .unwrap();
+    for (i, n) in ["placeholder-name", "1", "3"].iter().enumerate() {
+        w.append("class.added", json!({"id": i + 1, "name": n}))
+            .unwrap();
+    }
+    drop(w);
     let mut m = Mcp::start(&dir, "1000000.00");
     // An account whose code is its own id.
     let first = m.ok(
@@ -3286,24 +3296,16 @@ fn references_resolve_unless_truly_ambiguous() {
         json!({"entry_id": e, "account": first.to_string(), "side": "debit", "amount": "5.00"}),
     );
 
-    // A class named by its own id.
-    let c = m.ok("books.add_class", json!({"name": "placeholder-name"}))["id"]
-        .as_u64()
-        .unwrap();
-    let c2 = m.ok("books.add_class", json!({"name": c.to_string()}))["id"]
-        .as_u64()
-        .unwrap();
+    // Class 2 is named "1", class 1's id.
+    let c = 1u64;
     // "c" is class c's id and class c2's name: ambiguous.
     m.refuse(
         "books.add_line",
         json!({"entry_id": e, "account": "4000", "side": "credit", "amount": "5.00",
                "class": c.to_string()}),
     );
-    // c2 named by its own id: only one class is meant.
-    let c3 = m.ok("books.add_class", json!({"name": (c2 + 1).to_string()}))["id"]
-        .as_u64()
-        .unwrap();
-    assert_eq!(c3, c2 + 1, "classes number in order");
+    // c3 named by its own id: only one class is meant.
+    let c3 = 3u64;
     m.ok(
         "books.add_line",
         json!({"entry_id": e, "account": "4000", "side": "credit", "amount": "5.00",

crates/ledger-mcp/tests/spec_mcp.rs

@@ -775,6 +775,16 @@ fn happy_path(name: &str) -> Mcp {
     // Classes, parties, 1099.
     m.ok("books.add_class", json!({"name": "Rondo"}));
     m.ok("books.list_classes", json!({}));
+    m.ok(
+        "books.add_project",
+        json!({"name": "Harbor app", "kind": "on_spec", "started_on": "2026-01-05"}),
+    );
+    m.ok(
+        "books.update_project",
+        json!({"project": "Rondo", "kind": "internal", "description": "The Rondo app"}),
+    );
+    m.ok("books.projects", json!({}));
+    m.ok("books.project", json!({"project": "Rondo"}));
     let vendor = m.ok("books.add_vendor", json!({"name": "Landlord"}))["id"]
         .as_u64()
         .unwrap();
@@ -2194,15 +2204,12 @@ fn inv6_ambiguous_vendor_reference_refused() {
 fn inv6_ambiguous_class_reference_refused() {
     let dir = test_dir("inv6-class");
     let toml = books_toml(&dir, "1000000.00", "");
+    old_classes(&dir, &["Alpha", "1"]);
     let mut m = Mcp::start(&dir, &toml);
     m.accounts(BASE_CHART);
-    let alpha = m.ok("books.add_class", json!({"name": "Alpha"}))["id"]
-        .as_u64()
-        .unwrap();
-    let named = m.ok("books.add_class", json!({"name": alpha.to_string()}))["id"]
-        .as_u64()
-        .unwrap();
-    assert_ne!(alpha, named);
+    let (alpha, named) = (1u64, 2u64);
+    // No new name of digits only.
+    m.refuse("books.add_class", json!({"name": "3"}));
     let e = m.draft("2026-06-01", "classy", &[]);
     // add_line with an ambiguous class is refused too, but writes the
     // line first: see add_line_bad_class_leaves_journal_unchanged.
@@ -2220,6 +2227,19 @@ fn inv6_ambiguous_class_reference_refused() {
     m.ok("books.profit_and_loss", json!({"class": "Alpha"}));
 }
 
+/// Books an earlier version wrote holding these classes, in id order: a
+/// name of digits only can't be added now (it would read as an id), so
+/// only old books hold the id/name pairs invariant 6 refuses.
+fn old_classes(dir: &Path, names: &[&str]) {
+    let books = dir.join("books-data");
+    drop(ledger_store::Store::create(&books, ledger_core::Currency::USD).unwrap());
+    let mut w = ledger_store::JournalWriter::open(&books.join(ledger_store::JOURNAL_FILE)).unwrap();
+    for (i, n) in names.iter().enumerate() {
+        w.append("class.added", json!({"id": i + 1, "name": n}))
+            .unwrap();
+    }
+}
+
 /// Invariant 2: a refused add_line leaves the journal unchanged, here when
 /// the line's class doesn't resolve (unknown, or ambiguous per invariant
 /// 6).
@@ -2227,10 +2247,9 @@ fn inv6_ambiguous_class_reference_refused() {
 fn add_line_bad_class_leaves_journal_unchanged() {
     let dir = test_dir("bug-class");
     let toml = books_toml(&dir, "25.00", "");
+    old_classes(&dir, &["Alpha", "1"]);
     let mut m = Mcp::start(&dir, &toml);
     m.accounts(BASE_CHART);
-    m.ok("books.add_class", json!({"name": "Alpha"}));
-    m.ok("books.add_class", json!({"name": "1"}));
     let e = m.draft("2026-06-01", "classy", &[]);
     for class in ["Nope", "99", "1"] {
         // Mcp::tool asserts the journal is unchanged on refusal.
@@ -2251,10 +2270,9 @@ fn add_line_bad_class_leaves_journal_unchanged() {
 fn profit_and_loss_by_class_validates_class() {
     let dir = test_dir("bug-pnl-class");
     let toml = books_toml(&dir, "1000000.00", "");
+    old_classes(&dir, &["Alpha", "1"]);
     let mut m = Mcp::start(&dir, &toml);
     m.accounts(BASE_CHART);
-    m.ok("books.add_class", json!({"name": "Alpha"}));
-    m.ok("books.add_class", json!({"name": "1"}));
     m.refuse("books.profit_and_loss_by_class", json!({"class": "Nope"}));
     m.refuse("books.profit_and_loss_by_class", json!({"class": "1"}));
 }

crates/ledger-mcp/tests/spec_vault.rs

@@ -2071,6 +2071,7 @@ fn idempotent_tools_change_nothing_when_repeated() {
         ("6300", "Insurance", "expense"),
     ]);
     m.add_party("Dana Employee", &["employee"]);
+    m.ok("books.add_project", json!({"name": "Harbor"}));
     let entry = m.post(
         "2026-02-01",
         json!({}),
@@ -2193,6 +2194,10 @@ fn idempotent_tools_change_nothing_when_repeated() {
             "books.set_fx_rate",
             json!({"currency": "EUR", "date": "2026-01-02", "rate": "1.10"}),
         ),
+        (
+            "books.update_project",
+            json!({"project": "Harbor", "kind": "client", "status": "paused"}),
+        ),
     ];
     let list = m.rpc("tools/list", json!({}));
     let marked: std::collections::BTreeSet<String> = list["result"]["tools"]