From 68ff3a8044d97618612420aa647207bc120a0278 Mon Sep 17 00:00:00 2001
From: satoshai-dev <262845409+satoshai-dev@users.noreply.github.com>
Date: Tue, 24 Feb 2026 18:26:56 +0000
Subject: [PATCH] fix: add CLI validation and improve error handling

- error on --output with multiple contracts (prevents silent overwrite)
- error on --stdout with multiple contracts (prevents invalid output)
- wrap fetch() to provide context on network errors
- wrap response.json() to handle malformed API responses

Closes #1, closes #2, closes #3, closes #4

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 .changeset/fix-cli-validation.md |  5 +++++
 src/commands/fetch.ts            | 12 ++++++++++++
 src/fetcher.ts                   | 19 +++++++++++++++++--
 3 files changed, 34 insertions(+), 2 deletions(-)
 create mode 100644 .changeset/fix-cli-validation.md

diff --git a/.changeset/fix-cli-validation.md b/.changeset/fix-cli-validation.md
new file mode 100644
index 0000000..4920343
--- /dev/null
+++ b/.changeset/fix-cli-validation.md
@@ -0,0 +1,5 @@
+---
+"@satoshai/abi-cli": patch
+---
+
+Add CLI validation for --output/--stdout with multiple contracts and improve fetch error messages
diff --git a/src/commands/fetch.ts b/src/commands/fetch.ts
index d03a7a0..528081d 100644
--- a/src/commands/fetch.ts
+++ b/src/commands/fetch.ts
@@ -50,6 +50,18 @@ export const fetchCommand = defineCommand({
 
     const contractIds = args.contract.split(',').map((s) => s.trim());
 
+    if (args.output && contractIds.length > 1) {
+      throw new Error(
+        '--output cannot be used with multiple contracts. Omit --output to write separate files, or use --stdout.',
+      );
+    }
+
+    if (args.stdout && contractIds.length > 1) {
+      throw new Error(
+        '--stdout cannot be used with multiple contracts. Fetch one contract at a time with --stdout.',
+      );
+    }
+
     for (const contractId of contractIds) {
       const { address, name } = parseContractId(contractId);
 
diff --git a/src/fetcher.ts b/src/fetcher.ts
index 18a1523..18de543 100644
--- a/src/fetcher.ts
+++ b/src/fetcher.ts
@@ -31,7 +31,15 @@ export async function fetchContractAbi(
   const baseUrl = resolveNetwork(network);
   const url = `${baseUrl}/v2/contracts/interface/${address}/${name}`;
 
-  const response = await fetch(url);
+  let response: Response;
+  try {
+    response = await fetch(url);
+  } catch (cause) {
+    throw new Error(
+      `Network error fetching ABI for ${address}.${name} on ${network}`,
+      { cause },
+    );
+  }
 
   if (!response.ok) {
     if (response.status === 404) {
@@ -44,5 +52,12 @@ export async function fetchContractAbi(
     );
   }
 
-  return (await response.json()) as ClarityAbi;
+  try {
+    return (await response.json()) as ClarityAbi;
+  } catch (cause) {
+    throw new Error(
+      `Invalid JSON response for ${address}.${name} on ${network}`,
+      { cause },
+    );
+  }
 }