send_image

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

With no annotations provided, the description carries the full burden and reveals the encryption process, OBS upload, immediate send, and honest failure modes if key resolution or upload is rejected, which is transparent for a mutation tool.

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 concise (4 sentences) and front-loaded with the core action, each sentence contributing essential information without redundancy.

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?

Given no output schema or annotations, the description adequately covers purpose, process, failure modes, and parameter usage, though it lacks details about return values or success confirmation, which is acceptable for a send operation.

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 coverage is 100%, so baseline is 3, but the description adds mutual exclusivity constraint for imagePath/imageBase64 and clarifies chatId is a LINE MID, providing meaningful extra guidance.

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 explicitly states the tool sends an E2EE image to a LINE conversation, detailing the process (encrypt → upload → send) and targeting 1:1/group/room chats, which clearly distinguishes it from sibling tools like send_message or send_sticker.

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 specifies the tool works for 1:1/group/room and requires exactly one of imagePath or imageBase64, but does not explicitly mention when not to use it or name alternatives, though the context of sibling tools makes it implicit.

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