repl_key

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

With no annotations provided, the description carries the full burden of disclosing behavioral traits. It only states the action itself and gives no information about session prerequisites, potential side effects (e.g., ctrl-c terminating a process), or return behavior. This is a significant gap for a tool that sends control keys.

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, direct sentence that front-loads the action and lists the allowed keys without any filler. Every word is informational, making it highly concise and well-structured.

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 two required string parameters, the description covers the core action and allowed inputs. However, the lack of annotations, output schema, and any mention of session state, error conditions, or effects leaves noticeable gaps, making it only minimally 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?

The schema has zero descriptions (0% coverage), so the description must compensate. It adds meaning to 'key' by explaining it is a control key and listing examples, and it implies 'id' refers to a session. However, it does not explicitly define the id parameter or state that key must be limited to the enumerated values, leaving partial ambiguity.

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 a specific verb 'Send' and identifies both the resource ('a session') and the nature of the input ('control key (enter/ctrl-c/ctrl-d/tab/arrows)'). This clearly distinguishes it from sibling tools like repl_send, which likely sends arbitrary text, by specifying the exact type of key input.

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 clear context by enumerating the supported control keys, indicating this is for sending special keys to a session. However, it does not explicitly name alternatives or state when not to use this tool, so it stops short of a 5.

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