Export current session cookies and localStorage as a Playwright storageState file, or return the JSON inline if no path is provided.
Export current session (cookies + localStorage) as a Playwright storageState. Saves to path, or returns the state JSON if path omitted.
| Name | Required | Description | Default |
|---|---|---|---|
| path | No | Output JSON file path. If omitted, returns the state inline. |
Changes observed during successful MCP inspections.
v1.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are present, so the description must carry the full burden. It discloses what is exported (cookies + localStorage) and the two output modes (file vs inline JSON), but does not mention prerequisites (live browser session), side effects (file overwriting), or confirm the operation is non-destructive.
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, information-dense sentences. The purpose and content are front-loaded, and the parameter branch is stated in one clause. No filler or redundancy.
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?
For a one-parameter tool, the description covers the action, the optional parameter behavior, and the return format. The absence of annotations leaves minor gaps around safety and prerequisites, but an agent can still invoke this tool correctly.
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 description coverage is 100% and the schema already contains the same behavioral note ('If omitted, returns the state inline'). The description adds no extra meaning beyond the schema, so 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 ('Export'), resource ('current session (cookies + localStorage)'), and output format ('Playwright storageState'). This clearly differentiates it from siblings like browser_storage_load and granular cookie/localstorage getters.
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?
The description implies a use case (saving/exporting session state) and the conditional path behavior, but it never explicitly says when to use this tool versus browser_storage_load, browser_cookie_set, or localStorage setters. No when-not guidance is provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.