Reads physical touch state, last coordinate, and queued synthetic tap count, providing a snapshot of the CYD's current input status for observation and diagnostics.
Machine-specific (cyd). Observation, L0. Read physical touch state, last coordinate, and queued synthetic tap count.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral burden, and 'Read' plus 'Observation' clearly indicate a non-mutating operation. It also discloses that it reports queued synthetic tap count, which is useful context. It does not mention potential side effects, but the read-only framing makes them unlikely.
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 sentence with no filler. It front-loads the read action and immediately lists the specific state components, making it easy for an agent to parse quickly.
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 zero-parameter state-read tool, the description is nearly complete: it names all observed data and labels the operation as observational. It does not specify return format or units, but the tool is simple enough that this is a minor gap rather than a blocker.
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 tool has zero parameters, so there is no parameter burden for the description to carry. The baseline for zero-parameter tools is 4, and the description adds relevant context about what data will be returned.
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 uses the specific verb 'Read' and names the exact resources: physical touch state, last coordinate, and queued synthetic tap count. It clearly identifies what the tool does, and the 'Observation' label helps distinguish it from mutating input tools like cyd_tap or cyd_input_clear, though it doesn't explicitly name a sibling.
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 phrase 'Observation, L0' implies this is a low-level read-only inspection tool, and 'Machine-specific (cyd)' suggests it is for that particular device. However, there is no explicit guidance about when to prefer this over cyd_input_read or other input-related tools, and no exclusions are stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.