snapshot

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

There are no annotations, so the description bears the full burden of behavioral transparency. It discloses the output format, size range, ref-based interaction model, and the URL-dependent behavior. It does mention that opening a URL will 'open and snapshot', which hints at a navigation side effect, but it does not clearly state whether this changes the current session, opens a new tab, or has any other lasting effect.

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?

The description is very compact: three short phrases carry the core purpose, the format, the size, how refs connect to session_click, and the url/no-url behavior. Every sentence earns its place and there is no filler or repetition.

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?

The description is mostly complete for a simple optional-parameter tool, but gaps remain: the 'limit' parameter is unexplained and the side effect of opening a URL is ambiguous. Since the output schema is present, the lack of return value details is not a concern. The overall information is enough to invoke the tool correctly in the common case, but not enough to fully understand edge cases.

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 0%, so the description must explain both parameters. It clarifies the behavior of the 'url' parameter: no URL uses the current session tab; with URL it opens and snapshots. But it says nothing about what 'limit' controls, making it an unexplained parameter that the agent cannot reason about effectively.

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 clearly identifies the output as a YAML-like tree of interactive elements with ref values, which is distinct from a screenshot or link list. It would be a 5 if it stated a direct verb like 'takes a snapshot' in the opening phrase, but the absence of a clear verb and explicit sibling differentiation keeps it at 4.

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 gives context for when to use it: no URL means the current session tab, and with a URL it opens and snapshots. It also shows how the refs should be used with session_click. However, it does not explicitly contrast the tool with alternatives such as session_text, session_links, or screenshot, so the agent must infer when snapshot is preferable.

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