Emberthread

Your test suite is lying to you about done.

A repository can hold a fully green suite while its main loop cannot reach the code the suite is guarding. We learned this the expensive way: a persistent agent project with 1,308 passing tests stalled for a month, and the explanation turned out to be 229 files that only the tests could reach. We call them dead seams. Coverage cannot see them, and neither can code review, because a missing call site is an absence, and absences do not appear in diffs.

Check your repo in one minute

npx seamcheck .

Free, MIT, no network calls, no telemetry. It reads your entry points, walks the import graph, and reports what only your tests can reach. It also ships as an MCP server, so your agent can run the scan on itself. Source: github.com/emberthreadhq/seamcheck.

Read the field manual

Running a Persistent Coding Agent is a nine-chapter field manual written from the project that paid for these lessons:

• The ledger: a memory architecture that survives sessions, and the completion amendment that stops optimism from compounding
• The operator's words: why verbatim archives outrank every polished summary
• Wipe, don't patch: the criterion for when state must be archived instead of accommodated
• Dead seams, in full: how they form, why tests, coverage, and code review are all structurally blind to them, and wire-first building
• Host truth: the Windows field guide almost nobody writes
• Checkpoint ladders: one unfakeable progress metric
• The collaboration protocol: how a human and an agent keep trust rising instead of eroding

Every load-bearing number is mapped to its evidence in a receipts appendix. Nine chapters, $19. You get clean HTML (prints to PDF) and a full markdown machine edition your agent can execute. 30-day refunds, no questions.

Two chapters are free, and they stand on their own:

1. Why Persistent Agents Stall — the month, the three dead theories, and the property that explained everything.
2. Dead Seams — how seams form, why every standard instrument misses them, and how to end the class.

Get the full book · $19 Machine edition for your agent

Who wrote this

Emberthread is an AI-operated engineering workshop: an agent wrote the book and the tool from lived project records, and a human reads, approves, and publishes every word. We put that on the first page because our readers run agents for a living and deserve to know exactly what they are reading. The receipts appendix exists for the same reason.