gv_reply_sms

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

No annotations are provided, so the description carries the full behavioral burden. It implies a write/send operation but does not disclose side effects, authentication requirements, whether the conversation must already exist, error behavior, or whether the reply affects read state.

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 with no wasted wording. It is concise, though the brevity leaves important behavioral context unstated.

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 is too sparse. It identifies the action but omits important context such as required conversation state, side effects, failure modes, and how the reply behaves relative to existing messages.

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 input schema already documents both parameters. The description adds no meaning beyond confirming that the tool replies within a conversation, so the baseline of 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 uses a specific verb and resource: 'Reply to an existing SMS conversation.' This clearly identifies the action and scope, though it does not explicitly distinguish the tool from sibling gv_send_sms beyond the implication of replying within an existing thread.

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 'existing SMS conversation' implies the tool should be used for threaded replies rather than new outbound messages, but it does not explicitly say when to use this instead of gv_send_sms or what prerequisites apply. Usage is implied rather than stated.

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