get_chat_messages

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

No annotations provided so description carries full burden. It discloses E2EE decryption, resolved sender name, mediaType flag, mentions handling, and paging behavior thoroughly.

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?

Single paragraph, front-loaded with main action. Every sentence adds value, though could be slightly more structured (e.g., separate sections).

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 and tool complexity (paging, E2EE, mentions), description covers key behavioral aspects and return fields adequately.

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%. Description adds meaningful context beyond schema, such as E2EE decryption, fromName, and mentions as raw contentMetadata.MENTION, enhancing parameter understanding.

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?

Description clearly states 'Fetch messages from one LINE conversation' with specific verb and resource. It distinguishes from sibling tools like get_message_media by mentioning messageId for that purpose.

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?

Describes when to use `before` for paging and explains default behavior (most recent messages). Does not explicitly mention alternatives but provides clear usage context.

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