Link tinymemory-bus and add the TinyMemory module client seam

[senamakel]

What changed and why

TinyMemory ships as a loadable TinyBus module — a cdylib exporting one object
with 89 members on it. The host can load that binary but cannot use anything
out of it, so the member names, the payload types and the error-name table have
to arrive as an ordinary library. They now do.

• vendor/tinymemory submodule, pinned at the v1.1.0 tag — the release
  that introduced tinymemory-bus. Pinned at a tag rather than a main commit
  because a TinyMemory release is also what publishes the per-platform module
  archives and their checksum.toml; the library the host links has to be the
  one those archives were built from.
• tinymemory-bus = { path = "vendor/tinymemory/crates/tinymemory-bus" }. This
  is the only piece of TinyMemory the host links: no engine, no storage, no
  traits, no async runtime. Seven pure-Rust dependencies (serde,
  serde_json, chrono, sha2, uuid, anyhow, thiserror).
• src/openhuman/memory/driver/module/ — the client seam.

The client seam

MemoryModule binds the module's object over a tinybus::Proxy.
MemoryModule::call is public and reaches every member: pass a name from
tinymemory_bus::names::methods and the positional arguments as a tuple. Typed
wrappers cover the driver-level members (DriverId, Capabilities, Health,
Shutdown, OpenStore) and the mandatory core family (Store, Get,
Forget, List, Namespaces) — what a host needs to bind a driver and prove
it answers. The remaining families are one call each and get wrappers as the
driver seam grows into them.

OpenStore returns an object path, not a value — a sibling store under the
same workspace exporting the identical interface — so MemoryModule::at binds
one. OBJECT_PATH is the root object, not the only one.

The error mapping is the part worth reviewing

A TinyBus failure is a name plus prose. MethodFailed is the one that reached
the driver, and tinymemory_bus::wire::from_wire maps it back — the same table
the module mapped out through, which is what stops the two ends drifting into
disagreeing about what a name means. The case that matters is PathEscape: it
reports a symlink or traversal that left the workspace sandbox, and flattening
it into Invalid would turn a security-relevant refusal into a caller mistake.

Everything that is not a MethodFailed never reached the driver, so it is
reported as the transport fact it is rather than flattened into Other:

TinyBus error	becomes	why
Timeout	MemoryError::Timeout
NameHasNoOwner, Transport, Io	Unreachable	module not up yet — retryable
UnknownMethod/Object/Interface, IncompatibleVersion	Backend	version skew; the arguments were fine, so not Invalid
unrecognised error name	Other	a newer module may name an error this build has no variant for; answering Invalid would send a caller into a rewrite loop over correct input

Public API / behavior changes

Additive only. Nothing existing is touched: the diff is 7 files, and the only
edit to pre-existing code is memory/driver/mod.rs gaining pub mod module;
and a doc paragraph.

module is not a MemoryProvider impl and is not wired into driver
selection. It cannot be yet, and the module docs say so: embedded implements
the tinycortex_api contract this build pins, while module speaks the
tinymemory-bus vocabulary the loadable module was built against. At the
current TinyCortex pin those are unrelated types. They converge when the
TinyCortex pin moves to a revision that re-exports tinymemory-api.

Deliberately no [patch] entry yet

The natural companion would be:

[patch."https://github.com/tinyhumansai/tinymemory"]
tinymemory-api = { path = "vendor/tinymemory/crates/tinymemory-api" }
tinymemory-bus = { path = "vendor/tinymemory/crates/tinymemory-bus" }

It is not here, and that is deliberate rather than forgotten. The vendored
TinyCortex pin (ce98837) still defines the memory contract itself in
tinycortex-api; only newer revisions re-export tinymemory-api and pull it in
by git. Adding the patch now would make cargo warn about a patch matching
nothing in the graph.

It has to land in the same change that bumps the TinyCortex pin. Without it the
git copy and this path copy resolve as two distinct crates and MemoryEntry
from one is not MemoryEntry from the other — the exact failure TinyMemory's
own root manifest documents and patches around. The comment above the dependency
in Cargo.toml says this so the next person to move the pin finds it.

Validation

• cargo build --lib — pass
• cargo test --lib memory::driver::module — pass, 6 new tests
• cargo fmt -- --check — pass
• cargo clippy --lib --all-features — pass, no findings

cargo clippy --all-targets fails to compile tests/subconscious_fullstack_e2e.rs
(await in the non-async fn harness_with). Pre-existing and unrelated —
the file is byte-identical to main (diff <(git show main:...) ... is empty)
and nothing in this PR can affect it. Not fixed here; raising rather than
widening scope.

Related

Depends on tinyhumansai/tinymemory#74, merged and released as v1.1.0.

Summary by CodeRabbit

• New Features

  • Added support for connecting to TinyMemory as an external memory module.
  • Added memory operations for stores, entries, listings, namespaces, metadata, health checks, and lifecycle management.
  • Added support for targeting the root module or a specific store.

• Bug Fixes

  • Improved handling and reporting of memory, transport, timeout, and contract errors.

• Tests

  • Added coverage for error mapping and transport failure scenarios.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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Run ID: 7d28dcfe-ce37-4c22-971e-cef884ed8026

📥 Commits

Reviewing files that changed from the base of the PR and between 60775aa and 2c374fa.

⛔ Files ignored due to path filters (1)

• Cargo.lock is excluded by !**/*.lock

📒 Files selected for processing (6)

• .gitmodules
• Cargo.toml
• src/openhuman/memory/driver/mod.rs
• src/openhuman/memory/driver/module/mod.rs
• src/openhuman/memory/driver/module/mod_tests.rs
• vendor/tinymemory

Included review availability: Your plan provides up to 10 included reviews per hour; 7 remain after this review.

---

📝 Walkthrough

Walkthrough

The PR vendors the TinyMemory bus contract and adds a public MemoryModule client. The client supports typed driver and store operations, maps TinyBus failures to MemoryError, and includes error-mapping tests.

Changes

TinyMemory module driver

Layer / File(s)	Summary
Wire contract and driver wiring .gitmodules, vendor/tinymemory, Cargo.toml, src/openhuman/memory/driver/mod.rs	The repository adds the TinyMemory submodule, pins the vendored tinymemory-bus dependency, and exports the module driver.
Module client and typed operations src/openhuman/memory/driver/module/mod.rs	MemoryModule binds TinyBus objects and provides typed driver, store, entry, listing, and namespace operations.
Transport error mapping and validation src/openhuman/memory/driver/module/mod.rs, src/openhuman/memory/driver/module/mod_tests.rs	TinyBus failures map to distinct MemoryError variants. Tests cover wire errors, transport failures, unknown members, and message preservation.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Merge Risk: 🔵 Low · up to 2c374

The PR adds the TinyMemory client boundary and pins the dependency to the intended release. It is mergeable with explicit owner awareness that the repository’s signing or provenance policy for the vendored dependency still needs confirmation.

Sequence Diagram(s)

sequenceDiagram
  participant Client
  participant MemoryModule
  participant TinyBus
  participant TinyMemoryModule
  Client->>MemoryModule: invoke typed operation
  MemoryModule->>TinyBus: call member with serialized arguments
  TinyBus->>TinyMemoryModule: deliver TinyBus request
  TinyMemoryModule-->>TinyBus: return wire response
  TinyBus-->>MemoryModule: return response
  MemoryModule-->>Client: deserialize typed result

Loading

Suggested reviewers: al629176

Poem

A rabbit hops where TinyBus flows,
Typed calls bloom in tidy rows.
Errors keep their names and sound,
Stores and namespaces gather round.
The module door swings open wide.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the two main changes: linking tinymemory-bus and adding the TinyMemory module client seam.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 21 functions across 3 files. (3 skipped: 3 unsupported.)
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches 💡 1

⚔️ Resolve merge conflicts 💡

• Resolve merge conflict in branch tinymemory-bus

---

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[tinysweeper]

tinysweeper found nothing blocking. Approving.

$0.0000 · 0 in / 0 out · 667 embedded · openrouter/openai/text-embedding-3-small