browser_local_storage

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

The description discloses the three modes of operation, which is useful context beyond the name, but it says nothing about persistence across reloads, scoping to the current origin, or what happens to unrelated keys on clear. More importantly, the described 'clear' action deletes stored data while destructiveHint is false, giving the agent a contradictory safety signal for the most dangerous action.

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?

A single front-loaded sentence with no filler, listing the available operations before the scope qualifier. It is efficient, though arguably too terse to carry routing information.

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 full schema coverage the parameters are covered, but there is no output schema, so the description should have clarified what 'get' returns (value? null when absent?) and whether clear affects the whole origin or just this session. For a multi-mode tool this leaves a meaningful gap.

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%, so the schema already documents key/value/action/session_id semantics, including which are required per action. The description adds nothing beyond that, so the baseline of 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?

The description names a specific resource (localStorage), the three operations (read/write/clear), and the scope (current page context), which is well beyond a tautology. It does not explicitly distinguish itself from adjacent siblings such as browser_evaluate (which can also touch page storage) or browser_get_cookies/browser_set_cookies, so it stops 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?

There is no guidance on when to choose this tool over browser_evaluate, cookies tools, or direct JS execution, and no prerequisites are stated (e.g., that a page must be loaded/session established first). The three operations are implied by the verb list, but no when/when-not routing exists.

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