Recommended actions

• [Documentation problem | High] Clarify index attribute placement — Document that single-column field indexes use #[index(btree)] only, while named accessor = ... belongs on table-level multi-column indexes. Evidence: t_049_binary_storage.

Failure patterns

Inline single-column index accessor was misapplied (1 task)

• Classification: Documentation problem
• Confidence: High
• What the model wrote: #[index(btree, accessor = by_owner)] on pub owner: Identity
• What was expected: #[table(..., index(accessor = by_owner, btree(columns = [owner])))] with pub owner: Identity
• What the error says: publish_error: spacetime publish failed
• Why this happened: The supplied guidance showed table-level multi-column index accessors, but did not clearly state that inline field indexes do not accept accessor, so the model used the wrong syntax form.
• Suggested action: Clarify index attribute syntax and examples in rust-server/SKILL.md.
• Suggested area: rust-server/SKILL.md
• Affected tasks: t_049_binary_storage
• AI guidelines gap: Make the single-column #[index(btree)] form explicit and state that named accessor = ... is only used on table-level index definitions.

Right-semijoin arguments were reversed (1 task)

• Classification: Model limitation
• Confidence: Medium
• What the model wrote: ctx.from.member().right_semijoin(ctx.from.eligibility(), |member, eligibility| member.id.eq(eligibility.member_id))
• What was expected: ctx.from.eligibility().right_semijoin(ctx.from.member(), |eligibility, member| eligibility.member_id.eq(member.id))
• What the error says: semijoin_intersection: failed
• Why this happened: The model reversed the left/right query inputs and the callback parameter order, so the query no longer matched the expected returned row type.
• Suggested action: None
• Suggested area: None
• Affected tasks: t_062_semijoin_intersection
• AI guidelines gap: None

Scheduled-table state handling diverged from the reference pattern (2 tasks)

• Classification: Model limitation
• Confidence: Low
• What the model wrote:
  • t_071_scheduled_private: if let Some(existing) = ctx.db.job_result().id().find(job.result_id) { ... update(JobResult { status: "complete".to_string(), ..existing }) }
  • t_069_scheduled_materialization: if let Some(existing) = ctx.db.materialized_state().id().find(1) { ... update(MaterializedState { status: "ready".to_string(), version: 1, refreshed_at: ctx.timestamp, ..existing }) }
• What was expected:
  • t_071_scheduled_private: let mut result = ... .expect("job result missing"); result.status = "complete".into(); ctx.db.job_result().id().update(result);
  • t_069_scheduled_materialization: initialize or update the pending row, then mutate the found state in place and update it
• What the error says: publish_error: spacetime publish failed
• Why this happened: The generated reducers followed a different state lifecycle than the golden answers, and the publish step failed without a more specific compiler excerpt.
• Suggested action: None
• Suggested area: None
• Affected tasks: t_071_scheduled_private, t_069_scheduled_materialization
• AI guidelines gap: None

Custom struct/table schema did not match the golden shape (1 task)

• Classification: Model limitation
• Confidence: Low
• What the model wrote: #[derive(SpacetimeType)] pub struct Position { ... } and #[spacetimedb::table(accessor = entity, public)]
• What was expected: #[derive(SpacetimeType, Clone, Debug)] pub struct Position { ... } and #[table(accessor = entity)]
• What the error says: schema_parity: failed
• Why this happened: The generated schema diverged from the reference by omitting derives and changing the table annotation form, so the generated module no longer matched the expected shape.
• Suggested action: None
• Suggested area: None
• Affected tasks: t_003_struct_in_table
• AI guidelines gap: None

Join-view generation stopped mid-function (1 task)

• Classification: Model limitation
• Confidence: High
• What the model wrote: ... if let Some(customer) = ctx.db.customer().id().find(purchase.customer_id) { resul
• What was expected: A complete filter_map body producing OrderLineDetail
• What the error says: publish_error: spacetime publish failed
• Why this happened: The generated answer was truncated mid-expression, leaving invalid Rust and preventing publication.
• Suggested action: None
• Suggested area: None
• Affected tasks: t_061_three_table_join
• AI guidelines gap: None