session_navigate

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

Beyond the annotations, the description discloses important behavioral traits: navigation returns before the page settles, it reuses the active tab unless newTab is true, and it returns a {navigated} payload plus a newTab field when applicable. This is valuable context that the annotations alone do not provide, and it does not contradict the readOnlyHint, openWorldHint, idempotentHint, or destructiveHint values.

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?

Three focused sentences carry a full picture: purpose, tab behavior, return value, and asynchronous timing. The most important operational detail (return before page settles) is front-loaded near the end but clearly stated, and there is no redundant or filler content.

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?

Despite having no output schema, the description explains what is returned and the important timing caveat. For a simple 3-parameter tool with fully described schema properties and safety-relevant annotations, the description gives the agent everything needed to invoke it correctly and know what to expect next.

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?

The input schema has 100% parameter description coverage, so the baseline is 3. The description adds some context about active-tab reuse and returned fields, but it mostly reinforces what the schema already states rather than introducing new parameter semantics. It is adequate but not a major value-add over the schema.

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 opens with a specific verb and resource: 'Navigate a tab to a URL inside the user's authenticated session.' It clearly distinguishes this from sibling tools like session_read_page or session_screenshot by focusing on navigation and the authenticated-session context. The distinction between logged-in and signed-out behavior further clarifies the tool's unique purpose.

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 clear context on when to use the tool (navigating within an authenticated session) and provides sequencing guidance ('follow it with session_wait before reading'). It does not explicitly name alternatives or state when not to use it, but the guidance is sufficient for an agent to select this tool correctly in most cases.

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