agnt-store

SQLite message store for the agnt agent runtime.

Bundled SQLite persistence that implements agnt_core::MessageStore. WAL mode, prepared-statement cache, batch transactions, microsecond tool profiling, and token usage accounting built in.

[dependencies]
agnt-store = "0.2"

When to depend on this

Most users should cargo add agnt — the flagship crate re-exports this one under the store feature.

Depend directly on agnt-store when you want bundled SQLite persistence without agnt-core's Agent loop — for example, to persist messages from a custom agent implementation that uses the same on-disk schema.

What it provides

• Store::open(path) — open a SQLite store, auto-creates schema
• Store::load(session) — load all messages for a session
• Store::append(session, msg) — single message, single roundtrip
• Store::append_many(session, &[msg]) — batch in one transaction, one fsync
• Store::with_transaction(f) — arbitrary batching with automatic rollback
• Store::log_tool(session, name, args, result, duration_us) — persist a tool execution record
• Store::stats(session) — per-tool latency histograms (count, avg, max µs)
• Store::log_usage(session, idx, prompt, completion) — record token usage for an assistant turn
• Store::usage_total(session) — prompt/completion/total token totals
• Store::clear(session) — wipe a session
• Implements agnt_core::MessageStore

Performance

v0.2 improvements over v0.1:

• PRAGMA journal_mode=WAL + synchronous=NORMAL — batched fsync
• prepare_cached for every statement — no per-call SQL reparse
• append collapsed to one INSERT … SELECT COALESCE(MAX(idx),-1)+1 … (one roundtrip instead of two)
• append_many wraps N inserts in one transaction — N+2 fsyncs → 1

License

Dual-licensed under MIT OR Apache-2.0.