browser_click

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

With no annotations, the description carries the full burden and does so: the kernel re-queries the element's live position, refuses if the element is gone/moved/covered, and explicitly "does not pretend to succeed." It also discloses that x/y bypasses these safety checks.

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 sentences, front-loaded with the primary mechanism, then the fallback caveat. Every clause earns its place with no filler.

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 mutation tool with no annotations and no output schema, the description covers the critical behavior (refusal semantics, live-position check) well. Minor gaps remain around what a successful click returns or coordination with snapshotId freshness, but nothing an agent needs to call it correctly is missing.

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 already documents all 8 params, so baseline is 3; the description adds real value on emsn persistence ("keeps its emsn while the page stays") and the x/y checks skipped, beyond the schema text. Other params (button, clickCount, tabId) are left to 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?

States a specific verb (Click) and resource (an element by its emsn from the latest snapshot) and immediately distinguishes the two targeting modes (emsn vs x/y). An agent can tell exactly what this does without opening the schema.

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?

"prefer emsn" and "Passing x/y instead skips all of that checking" gives a clear selection rule between the two targeting modes. It doesn't explicitly contrast against sibling tools like browser_move or browser_drag, keeping it shy of a 5.

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