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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses high-integrity process injection, human-like press duration (default 120ms), and states that it returns success/failure. This goes beyond a simple 'click' description and gives the agent useful behavioral traits.

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 two sentences, front-loaded with the primary action and resource. Every clause adds value: the coordinate system, the injection method, the press behavior, and the return value. No wasted words.

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 click tool with 4 parameters and no output schema, the description covers the purpose, key behaviors, and return value. It lacks explicit edge-case handling (e.g., off-screen coordinates) but is otherwise complete enough for correct invocation.

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%, so the baseline is 3. The description adds almost nothing beyond the schema: it repeats the physical pixel coordinate framing and the default hold duration, both already in the schema. No new parameter meaning is introduced.

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 states a specific verb and resource: 'performs a mouse click at specified physical pixel coordinates'. It differentiates from the sibling desktop_click_target by explicitly saying the click is at raw physical pixel coordinates, not a located target.

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 implies when to use the tool (when you have physical pixel coordinates to click) but does not explicitly mention when not to use it or point to alternatives like desktop_click_target or desktop_locate. The 'high integrity process injection' hint adds context but no clear routing guidance.

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

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

No annotations are provided, so the description carries the full burden. It discloses the order of operations (visual localization then click), mentions multi-stage precision, and states it returns coordinates and click result. However, it does not disclose potential failure modes (e.g., target not found), side effects (e.g., moving the cursor), or any access/permission requirements. This is a gap given no annotation support.

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 a single, front-loaded sentence that conveys the core purpose, the steps, and the return value without redundancy. It is appropriately sized and contains no wasted words.

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 tool that combines two actions (locate and click) with three parameters, no output schema, and no annotations, the description is minimal. It explains the process and return but lacks usage guidance relative to siblings, error handling, and behavior when the target is not found. This leaves the agent without enough context to fully anticipate the tool's behavior in 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 100%, with each parameter (target, hold_ms, image_path) having a description. The tool description adds no additional parameter semantics beyond what the schema provides; it only mentions the overall return value. Therefore, the description does not compensate for any missing schema detail.

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 states the tool's purpose: '定位目标并点击一步完成' (locate target and click in one step), specifying that it first performs visual localization (multi-stage precise localization) then a mouse click, and returns coordinates and click result. This distinguishes it from siblings like desktop_click (click only) and desktop_locate (locate only).

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 implies the tool performs both locate and click, but it does not explicitly state when to use this over the sibling tools. There is no mention that desktop_locate should be used if only coordinates are needed, or that desktop_click should be used if the target is already known. Guidance is only implied by the combined action.

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

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

With no annotations provided, the description must carry the full behavioral burden. It discloses the multi-stage refinement process and ±5px accuracy, which is useful, but it does not explicitly state whether the tool is read-only (no state changes) or what happens on failure (e.g., element not found). The mention of auto-screenshot via optional image_path is implicit but not fully explicit.

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 a single, efficient sentence in Chinese that front-loads the core purpose (locate UI element, return coordinates) before diving into methodology. No wasted words, though it could be slightly more structured with a period after the main clause.

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 locate tool with 100% parameter coverage and no output schema, the description covers the key aspects: what it does, method, accuracy. However, it omits failure behavior (e.g., if the target is not found) and does not clarify whether the tool performs any side effects (it likely doesn't, but this is not stated). The missing output schema shifts some burden to the description, but the core usage is adequately covered.

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 covers all parameters with descriptions, so the baseline is 3. The tool description adds context about the refinement process that relates to the 'refine' parameter, but it does not add meaning beyond what the schema already states for target and image_path. The schema descriptions are sufficient.

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 states the action (locate), the resource (a UI element/text/button in a screenshot), and the output (physical pixel coordinates x,y). It is distinct from sibling tools like desktop_click (clicking) and desktop_screenshot (capturing), making its purpose unambiguous.

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 provides no guidance on when to use this tool versus alternatives, nor does it mention any exclusions or prerequisites. An agent cannot infer when to prefer desktop_locate over desktop_click_target or other siblings based on the description alone.

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

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

No annotations are provided, so the description must carry the full behavioral disclosure. It does state the primary behavior, file format, and return value. However, it does not disclose side effects such as overwriting existing files, whether the path is expected to be absolute or relative, or any permission/system requirements.

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 a single, compact sentence that front-loads the action, format, and return value. There is no filler or repetition of schema details.

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 tool with one optional parameter and no output schema, the description adequately covers the key facts: what is captured, the saved format, and the returned value. It could add edge-case behavior such as error handling or path creation, but the core contract is complete.

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%, with the path parameter already documented as optional and defaulting to a temporary directory. The tool description adds the overall PNG-saving context but does not add parameter-specific meaning beyond what the schema already provides, so baseline 3 is appropriate.

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 states a specific verb, resource, and outcome: take a full-screen screenshot, save it as a PNG, and return the file path. This also distinguishes it clearly from the sibling tools (desktop_click, desktop_locate, desktop_click_target), which perform different actions entirely.

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 makes the use case clear: capturing the full screen to a PNG file. It does not explicitly mention when not to use it or name an alternative, but the sibling tools are action-type tools, so there is little ambiguity about when this screenshot tool is appropriate.

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