Three regressions shipped in 0.10.0 share one failure shape: an empty result
with a success status, indistinguishable from "nothing found" for the LLM
clients that are cbm's primary consumers.
1) structuredContent {} on the whole tree-format surface (#1522 bug 1).
#1488 replaced the duplicated payload with an EMPTY structuredContent
object while every tool still declared a blanket permissive outputSchema.
Spec-honoring clients (Claude Code among them) treat structuredContent as
THE result when a schema is declared, so search_graph, trace_path,
query_graph, get_architecture, search_code, and detect_changes all rendered
as literally "{}" on their DEFAULT format, on every platform. The corrected
contract: no tool declares an outputSchema (tool output is
format-parameter-polymorphic — no static schema is truthful), JSON-object
payloads keep their parsed structuredContent, errors keep
structuredContent.error, and text-shaped payloads carry NO structuredContent
key at all — which also preserves #1375's no-duplication win.
2) Frontend queue overflow killed the session (found by the #1522 sweep).
Any 7+ requests pipelined in one stdin burst — an agent issuing parallel
tool calls does exactly this — overflowed the 8-frame frontend queue, which
failed the whole session: rc=1 with ZERO bytes of output, every buffered
response lost. A full queue is now backpressure: the stdin reader blocks
until the worker drains (bounded by the same stop/fail flags every teardown
path already sets); only a single frame larger than the entire 12 MiB byte
budget — which could never be admitted — remains a hard failure.
3) config get printed "" with exit 0 for every unset and every unknown key
(#1522 bug 2). list printed stored-or-DEFAULT while get printed
stored-or-EMPTY, and no subcommand validated key names, so a typo was
indistinguishable from a correctly-read setting. One config-key table now
drives help, list, get, set, and reset: get prints the stored value or the
key's real default (the same fallback the runtime readers use), and unknown
keys error with exit 1 on get, set, and reset alike.
Tests — each RED on the pre-fix tree and RED again on revert:
* test_mcp.c: text results carry no structuredContent key; tools/list
declares no outputSchema; the tool-table guard now binds all three
branches (absent / parsed-object / error) for every registered tool.
* test_daemon_frontend.c: the over-capacity contract flips from
"session fails" to "backpressure without loss" — the held first request
plus all 32 over-capacity frames are answered and the run closes cleanly.
* test_cli.c: the config command contract — defaults, round-trip, reset,
and unknown-key rejection on all three subcommands.
* smoke-test.sh: Phase 3z rewritten to the corrected structuredContent
contract, new Phase 3z1 (default-format replies usable in schema-honoring
clients, no outputSchema advertised), 3z2 (24 pipelined calls all
answered), 3z3 (config defaults + unknown-key rejection) — all asserted
against the SHIPPED artifact, where #1488's smoke phase previously pinned
the empty-object behavior as correct.
Verified end-to-end on the locally built production binary: all 15 tools
declare no schema; text tools return ABSENT structuredContent, object tools
populated, error envelopes intact; 7/24/64-deep pipelined bursts all answered
with rc=0; config get prints real defaults and exits 1 on unknown keys.
hook_augment (structuredContent.projects) and index_resilience
(structuredContent.status) consume object payloads and are unaffected.
Fixes#1522.
Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>