Save browser state

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

Annotations already declare destructiveHint=true, readOnlyHint=false, idempotentHint=false and openWorldHint=true, so safety is covered structurally. The description earns credit for enumerating exactly which storage areas are captured and that sessionStorage is deliberately dropped — a real behavioral constraint beyond the annotations. It does not restate the overwrite behavior, which lives in the path schema.

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, front-loaded with the contents and format, with the exclusion clause placed where it reads as a qualifier. No filler whatsoever.

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 two-parameter write tool with full schema coverage and destructive annotations, the description supplies the one thing the schema cannot: what state is and isn't captured. The only minor omission is the round-trip relationship to browser_load_state, which an agent restoring state would want stated.

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 path parameter already documents relative-to-working-directory, overwrite, and parent-must-exist semantics, plus session_id ties back to browser_open. The description adds no parameter-level detail, 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 (Save) and a precisely enumerated resource (cookies, local storage, IndexedDB) plus the output format (Playwright-compatible JSON). The explicit exclusion of sessionStorage further sharpens scope. It does not, however, name its inverse sibling browser_load_state, so the pairing must be inferred from the shared 'state' naming.

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 says what is captured but never when to use this instead of alternatives; the obvious pairing with browser_load_state for persist/restore workflows is left unstated. No preconditions (an open session, a writable host path) are mentioned in the description itself.

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