feat: tx add --dry-run to validate before writing (v0.3.3)

An agent importing rows in a loop could fail mid-batch: a --to account that
didn't exist yet errored after earlier rows had already been written, leaving
a half-applied batch to clean up by hand.

--dry-run resolves --from/--to and infers the type but sends nothing, printing
{"dry_run": true, "would_send": {...}}. A missing account stays a hard error
(exit 1) so the agent can dry-run every row first, create the accounts the
errors name, then run the batch for real. No batch input mode: the agent
already owns the loop.

Verified live read-only: valid accounts emit would_send and write nothing
(search confirms []), missing account exits 1 with the candidate list.

PATCH: new optional flag, contract unchanged.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

1 files changed, 9 insertions, 1 deletions

diff --git a/SKILL.md b/SKILL.md
index 672c97e..42d5fb4 100644
--- a/SKILL.md
+++ b/SKILL.md
@@ -56,7 +56,7 @@ firefly account balance <name|id> [--at YYYY-MM-DD]
 firefly account create <name> --type asset|expense|revenue
         [--opening-balance N] [--currency CODE]
 firefly tx add <amount> --from <acct> --to <acct>
-        [--desc TEXT] [--date YYYY-MM-DD] [--category NAME] [--tags a,b] [--type T]
+        [--desc TEXT] [--date YYYY-MM-DD] [--category NAME] [--tags a,b] [--type T] [--dry-run]
 firefly tx edit <id>
         [--amount N] [--date YYYY-MM-DD] [--desc TEXT] [--from <acct>] [--to <acct>]
         [--category NAME] [--tags a,b] [--type T]   # only fields passed are changed
@@ -102,6 +102,14 @@ Supports asset, expense, revenue. asset accounts get the default role
 automatically. Unlike categories/tags, accounts are NOT auto-created by
 `tx add`, create them explicitly here first.
 
+**Validate a batch before writing any of it:** when importing many rows in a
+loop, a mid-batch failure (a `--to` account that doesn't exist yet) leaves the
+earlier rows already written. Dry-run each row first so the whole batch fails
+fast: `tx add ... --dry-run` resolves `--from`/`--to` and infers the type but
+sends nothing, printing `{"dry_run": true, "would_send": {...}}`. A missing
+account is still a hard error (exit 1). Recipe: dry-run every row, create any
+accounts the errors name, then run the batch for real.
+
 **Check a balance:**
 ```bash
 firefly account balance test01            # -> {"id","name","current_balance"}