Release an agent-controlled browser tab back to the user without closing it by removing ownership and detaching the debugger.
Gives the tab back to the user without closing it (ownership removed, debugger detached). For an adopted tab, or an orphan tab of my agent.
| Name | Required | Description | Default |
|---|---|---|---|
| tab_id | Yes | Your tab's id (from browser_new_tab, or a tab adopted with browser_adopt_tab). |
Changes observed during successful MCP inspections.
v2.31.6Output schema / (root)Previous value: -{
- "properties": {
- "result": {
- "title": "Result",
- "type": "string"
- }
- },
- "required": [
- "result"
- ],
- "title": "browser_release_tabOutput",
- "type": "object"
-}New value: +nullv0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare idempotentHint=true and destructiveHint=false, so the description earns credit for the state semantics it adds: ownership is removed, the debugger is detached, and the tab survives. It doesn't say what practical consequence follows (e.g. that the agent must re-adopt before further control), so not a 5.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two short sentences with the key constraint ("without closing it") and the state effects front-loaded in parentheses. The trailing fragment "or an orphan tab of my agent" is slightly elliptical but carries real routing information, so no waste is present.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
With one fully described parameter, no output schema, and annotations covering the safety profile, the description covers what an agent needs to select and invoke it. The one remaining gap is not stating the post-release consequence for future tool calls, which would make it airtight.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100% and the single tab_id parameter is fully documented in the schema, including its provenance (browser_new_tab or browser_adopt_tab). The description adds nothing about the parameter, so the baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb and resource ("gives the tab back to the user") and immediately delimits it from the obvious sibling by saying "without closing it", which lets an agent separate it from browser_close_tab. It does not name that sibling explicitly, so it falls short of a 5.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
"For an adopted tab, or an orphan tab of my agent" gives a clear condition for when this tool applies, which is more than most sibling tools offer. It stops short of naming browser_close_tab as the alternative and saying when not to release (e.g. while still mid-task), so no explicit exclusion set.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.