touch-browser

by nangman-infra

Overview Schema Source Related Servers Discussions Admin

Rust

Local

Close Session Tab

tb_tab_close

Close a tab in a browser session and update the active tab if needed.

Instructions

Close one daemon tab and update the active tab if needed.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "sessionId": "<sessionId>",
      "tabId": "<tabId>"
    },
    "name": "tb_tab_close"
  }
}

Input Schema

Name	Required	Description	Default
`sessionId`	Yes	The browser session to use for this operation.
`tabId`	Yes	The specific tab to use inside the session. If omitted, the active tab is used.

Output Schema

Name	Required	Description	Default
`sessionId`	Yes
`tabId`	Yes
`removed`	Yes
`removedState`	Yes
`activeTabId`	Yes
`remainingTabCount`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed3 schema fields changedv0.7.0Jun 12, 2026

addedInput schema / properties / sessionId / description

Added value: +"The browser session to use for this operation."

addedInput schema / properties / tabId / description

Added value: +"The specific tab to use inside the session. If omitted, the active tab is used."

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "additionalProperties": false,
+  "properties": {
+    "activeTabId": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "remainingTabCount": {
+      "minimum": 0,
+      "type": "integer"
+    },
+    "removed": {
+      "type": "boolean"
+    },
+    "removedState": {
+      "type": "boolean"
+    },
+    "sessionId": {
+      "type": "string"
+    },
+    "tabId": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "sessionId",
+    "tabId",
+    "removed",
+    "removedState",
+    "activeTabId",
+    "remainingTabCount"
+  ],
+  "type": "object"
+}

First observedv0.1.11Apr 15, 2026

TDQS

C2.6/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Only states that it 'update[s] the active tab if needed,' but no details on side effects (e.g., closing last tab, session impact). With no annotations, this is insufficient. Additionally, description implies tabId is optional while schema requires it, causing confusion.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness3/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Single sentence, no wasted words, but missing critical context. Conciseness is good but at the expense of completeness.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the output schema exists (not shown) and sibling tools, the description should clarify how this tool interacts with tab selection and session state. Current description is too minimal for safe invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema provides descriptions for both parameters (100% coverage), but the description contradicts the schema by suggesting tabId can be omitted. This undermines clarity and adds no extra value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly identifies the action 'close one daemon tab' and mentions updating the active tab. It distinguishes from sibling tools like tb_tab_list and tb_tab_open, though 'daemon tab' is jargon that may cause confusion.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance on when to use this tool versus alternatives like tb_tab_select or tb_session_close. The agent receives no context about prerequisites or typical use cases.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.