feat: add Puppeteer MCP suite (7 assertions, 1 bug found)

7 tools discovered, 7 assertions. 1 bug: puppeteer_navigate
crashes with internal error on invalid URLs instead of returning
isError. Fix PR submitted (modelcontextprotocol/servers#4051).
Server #40.

Author: blackwell-systems

examples/puppeteer-mcp/click_nonexistent.yaml

@@ -0,0 +1,11 @@
+name: puppeteer_click returns isError for nonexistent selector
+server:
+  command: npx
+  args: [-y, "@modelcontextprotocol/server-puppeteer"]
+assert:
+  tool: puppeteer_click
+  args:
+    selector: "#nonexistent-element"
+  expect:
+    is_error: true
+timeout: 15s

examples/puppeteer-mcp/evaluate_script.yaml

@@ -0,0 +1,11 @@
+name: puppeteer_evaluate runs JavaScript on page
+server:
+  command: npx
+  args: [-y, "@modelcontextprotocol/server-puppeteer"]
+assert:
+  tool: puppeteer_evaluate
+  args:
+    script: "document.title"
+  expect:
+    not_error: true
+timeout: 15s

examples/puppeteer-mcp/fill_nonexistent.yaml

@@ -0,0 +1,12 @@
+name: puppeteer_fill returns isError for nonexistent selector
+server:
+  command: npx
+  args: [-y, "@modelcontextprotocol/server-puppeteer"]
+assert:
+  tool: puppeteer_fill
+  args:
+    selector: "#nonexistent-input"
+    value: "test"
+  expect:
+    is_error: true
+timeout: 15s

examples/puppeteer-mcp/hover_nonexistent.yaml

@@ -0,0 +1,11 @@
+name: puppeteer_hover returns isError for nonexistent selector
+server:
+  command: npx
+  args: [-y, "@modelcontextprotocol/server-puppeteer"]
+assert:
+  tool: puppeteer_hover
+  args:
+    selector: "#nonexistent-element"
+  expect:
+    is_error: true
+timeout: 15s

examples/puppeteer-mcp/navigate_invalid_url.yaml

@@ -0,0 +1,12 @@
+name: "BUG: puppeteer_navigate crashes on invalid URL (should return isError)"
+server:
+  command: npx
+  args: [-y, "@modelcontextprotocol/server-puppeteer"]
+assert:
+  tool: puppeteer_navigate
+  args:
+    url: "not-a-valid-url"
+  expect:
+    is_error: true
+timeout: 15s
+skip: true  # Known bug: returns -32603 internal error instead of isError. PR #4051.

examples/puppeteer-mcp/screenshot_default.yaml

@@ -0,0 +1,12 @@
+name: puppeteer_screenshot captures default page
+server:
+  command: npx
+  args: [-y, "@modelcontextprotocol/server-puppeteer"]
+assert:
+  tool: puppeteer_screenshot
+  args:
+    name: "test-screenshot"
+  expect:
+    not_error: true
+    not_empty: true
+timeout: 15s

examples/puppeteer-mcp/select_nonexistent.yaml

@@ -0,0 +1,12 @@
+name: puppeteer_select returns isError for nonexistent selector
+server:
+  command: npx
+  args: [-y, "@modelcontextprotocol/server-puppeteer"]
+assert:
+  tool: puppeteer_select
+  args:
+    selector: "#nonexistent-select"
+    value: "option1"
+  expect:
+    is_error: true
+timeout: 15s