Send keys

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

With no annotations, the description carries the full burden. It adds one genuinely useful behavioral fact — keys go to the focused element — but is silent on what happens when nothing is focused, whether the call blocks or waits, and how modifier sequences are handled.

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, with the core action stated first and the disambiguation second. Every clause earns its place and nothing is padded.

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 two-parameter input tool with no output schema, the description supplies purpose plus the key routing decision, which is most of what an agent needs. Only the preconditions around focus and blocking behavior remain unaddressed.

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 schema already documents both 'keys' (with key-name examples) and 'repeat'. The description adds no syntax, ordering, or default details beyond that, 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 and resource ('Send individual key presses / keyboard shortcuts') and scopes it to 'the focused element'. It also explicitly separates itself from the nearest sibling by name, so an agent can pick it over browser_type without opening a 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?

Gives clear routing guidance: 'For typing literal text prefer browser_type.' This covers the primary confusion case but names only one alternative and gives no exclusions or prerequisites (e.g. how it relates to browser_fill or whether the page must be focused first).

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