[mforce]

Closes #843

Track A slice 2 of #514, stacked on #879 (retarget to main after it merges). Enforcement only, no src/ change.

What it adds

A tier is a dated exemption: a namespace, a privilege a module may not otherwise have, the surface that maps it, a reason and a reviewBy issue. The ledger gains one adapterTiers row today, Cluckwork.Api.Mcp → DirectRepository, surfaced by MapMcp, reviewed by #806. It is committed dormant: green now, with no /mcp and no tool class in the tree, so the ledger is not wrong the day #806 lands.

AdapterTierScanner (syntax-only, same walk as the sibling guards) fails on:

• a [McpServerToolType] type outside every tier namespace,
• a MapMcp call with no tier row (prints the JSON row to add),
• a tier row missing a field, with a privilege outside the closed set, or with a reviewBy that is not #NNN (an exemption with no end date).

A tier also unions into the reach ratchet's adapter roots and its persistence-forbidden set, so a tool class's repository parameters still need an adapters row and an AppDbContext parameter still fails.

Mutations run against the real tree (each red before it was claimed, then reverted)

Mutation	Result
[McpServerToolType] class Probe under Cluckwork.Api.Endpoints	red, tool type outside every tier
app.MapMcp("/mcp") in Program.cs with the tier row removed	red, mapped surface with no row; output prints the row
reviewBy removed from the row	red, registry error
WaterTools(IWaterUsageRepository) under Cluckwork.Api.Mcp	red, undeclared reach WaterTools.ctor → GeneralInventory
same class taking AppDbContext	red, forbidden persistence type

Why syntax, not EndpointDataSource

The issue suggested keying the tier on EndpointDataSource. The ledger guards live in the Application test project with no host, and the reach ratchet already finds top-level routes by scanning Map* calls in Program.cs; a MapMcp scan is the same mechanism. The decision record covers this and the other rejected shapes.

Scope against the issue

The issue's second bullet, owner rows for the four OpenIddict tables, is delivered by #877, not here: the table-owner guard fails #795's PR the moment it maps a table with no owner row, so the rows are written there by that author. The "add a mapped table with no owner row → red" criterion is therefore met on main already. The remaining criteria are the four mutations above.

For #806's author

Put tool classes under Cluckwork.Api.Mcp, add their adapters rows when the ratchet prints them, and delete AdapterTierRealTreeTests.McpTierRow_IsDormantToday, which goes stale on purpose.

Tests: Architecture and Documentation filter 246/246 (was 244). Full solution builds warnings-as-errors clean.

[coderabbitai]

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Run ID: c1f5f45c-ad0e-4487-8f07-ab45cbeb29d6

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[mforce]

Review round 1 (Codex gpt-5.6-sol, reviewer of record), head d61836a: changes requested, 3 findings, all accepted.

1. P2, surface is not validated. A row with surface: "MapMcpTypo" passes the registry, stays Dormant, and still grants its namespace the exemption. Fix in flight: the known surfaces become one shared closed set the registry validates against, with a test that an unknown surface is a registry error.
2. P2, a using alias hides the attribute. using ToolMarker = ModelContextProtocol.Server.McpServerToolTypeAttribute; plus [ToolMarker] outside the tier stays green; confirmed by the reviewer against the real tree. Fix in flight: file, namespace-block and global using aliases are resolved syntactically before the match, with fixture tests for each form and a real-tree mutation.
3. P3, inactive #if branches are not walked. The fixed parse-symbol list is shared with the three sibling ledger scanners since test(arch): module ledger and cross-owner edge ratchet (#842) #872. Rather than guess symbols, the fix adds a trust check: any <DefineConstants> in a src project that the parse options do not know is red, telling the author which symbol to add. No project defines one today, so it is green now. Recorded as a limit in the decision record.

Fix commits and the mutation evidence follow on this PR; round 2 goes back to the same reviewer.

[mforce]

Round 1 fixes pushed, and the branch is replayed onto main after #879 merged (d61836a → 7cae308).

Finding	Fix	Commit	Verification
1 surface unvalidated	AdapterTier.KnownSurfaces is one map from surface to the privilege it grants; the registry validates a row's surface against it and the scanner's call walk reads the same map	f46f1dd	UnknownSurface_IsRegistryError
2 using alias hides the attribute	file, namespace-block and global using aliases are resolved syntactically (global ones per project) before the attribute match	c503762	three fixture tests; real-tree mutation with a local alias to a locally declared McpServerToolTypeAttribute went red ToolTypeOutsideTier
3 inactive #if branches	ModuleLedgerScanner.UndeclaredDefineConstants reads <DefineConstants> from every src project and the root props file; any symbol the parse options do not carry fails the walk with the symbol to add. No project defines one today	bd6a2d0	two fixture tests; real-tree mutation adding <DefineConstants>MCP</DefineConstants> to the Api project went red naming it

Also 7cae308 drops narration comments. Architecture and Documentation guards 252/252 (was 246). Round 2 goes to the same reviewer on this head.

[mforce]

Review round 2 (Codex gpt-5.6-sol), head 7cae308: changes requested, 3 findings, all accepted. Round-1 fixes 1 and 2 verified complete by the reviewer's own re-run of its mutations; fix 3 verified but incomplete.

1. P2, the define-constant check misses src/Directory.Build.props and imported .props files. MSBuild imports them automatically, so #if MCP code could compile unseen while the trust check stays green. Fix in flight: no import resolution; the check over-approximates instead and reads every .csproj, .props and .targets in the repo, red on any unknown constant wherever and under whatever condition it sits. Mutations for both file forms.
2. P2, alias chains. using A = ...McpServerToolTypeAttribute; using B = A; and [B] outside the tier still hid the type. Fix in flight: alias targets resolve to a fixed point within scope, bounded so a cycle terminates, with chain and cycle tests and a real-tree mutation.
3. P3, the surface-to-privilege map's values were never read. Fix in flight: a row's privilege must equal the privilege its surface maps to, and the allowed privilege set derives from the map.

Product-defect tally for the stop rule: round 1 found two real guard holes, round 2 found two more (props import, alias chain). The loop continues to round 3.

[mforce]

Round 2 fixes pushed (7cae308 → e255139).

Finding	Fix	Commit	Verification
1 props and imported files unseen	no import resolution; the check reads every .csproj, .props and .targets in the repo (skipping bin, obj, node_modules, .git, web) and is red on any unknown constant, Condition or not	75670ac	three fixture tests; real-tree mutations src/Directory.Build.props and tools/mcp.props defining MCP both went red
2 alias chains	alias targets resolve to a fixed point, local then global per hop, bounded by the alias count so a cycle terminates	e0fba9e	chain-of-two, global-then-local and cycle tests; real-tree two-alias chain outside the tier went red ToolTypeOutsideTier
3 map values unread	a row's privilege must equal KnownSurfaces[surface]; the allowed privilege set derives from the map's values; the suggested row reads the map	d085e52	PrivilegeDoesNotMatchSurfaceMapping_IsRegistryError; mutating the map value went red with two registry errors

e255139 drops narration comments. Guards 259/259 (was 252). Round 3 goes to the same reviewer on this head.

[mforce]

Review round 3 (Codex gpt-5.6-sol), head e255139: approve, 0 findings.

The reviewer re-ran its own round-2 mutations (a src/Directory.Build.props defining MCP; a two-alias chain outside the tier) and both went red as claimed, and it names the remaining gaps as exotic for this repo: an imported build file under a skipped generated or frontend directory, a directory-symlink cycle, or a generic or array type used as an attribute alias. Guards 259/259.

Review yield over three rounds: 9 findings, 9 fixed with tests and real-tree mutations, 0 dismissed. Rounds 1 and 2 each found real holes in the guard (alias forms, unvalidated surface, MSBuild constants); round 3 found none. Loop stopped at the approval per the review rules. Ready to merge once CI finishes.