session_navigate

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

With no annotations provided, the description carries the full disclosure burden. It does add value by disclosing the tab-reuse behavior ('Reuses the active tab unless newTab is true') and the authenticated-session context. But it is silent on whether the call blocks until the page finishes loading, what happens on timeout or invalid URLs, and how an unauthenticated session is handled — all material for a navavigation tool.

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 core action, and the tab-reuse caveat earns its place. Zero filler and nothing redundant with the schema.

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 simple 3-parameter flat tool this is close to adequate, but with no output schema and no annotations, the missing wait-for-load and failure semantics leave an agent guessing about sequencing. It should state whether navigation completes before returning so the agent knows when subsequent read or interact tools can be issued.

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% — url, tabId, and newTab all have meaningful schema descriptions. The description adds no new parameter-level detail (its newTab phrasing largely mirrors the schema text), 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 ('Navigate') and resource ('a tab ... in the user's authenticated session'), making the core action unambiguous. The second sentence adds the tab-reuse behavior, but it does not explicitly distinguish itself from the closest siblings like session_click or session_read_page.

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?

'Navigate a tab to a URL' implies the use case — directly loading a URL in the browser — which is reasonably clear. However, there is no explicit when-not-to-use guidance or routing to alternatives such as session_click for link-based navigation.

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