discord_create_pin

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

Goes beyond the annotations by naming the required bot permissions (View Channel, Pin Messages) and confirming retry safety ('safe to retry'), which reinforces idempotentHint=true with practical context. It does not cover edge cases an agent could hit, such as pinning an already-pinned message or the per-channel pin limit, so it falls short of a 5.

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?

Three tight sentences: purpose first, then usage/alternatives, then behavior and permissions. Every clause carries information and the most decision-relevant content is front-loaded.

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 two-required-parameter mutation with an output schema and full annotation coverage, the description supplies what structured fields cannot: permissions and retry safety. Only the missing edge-case behavior (already pinned, pin cap) keeps it from being fully 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?

Schema coverage is 100%, so channel_id and message_id are already fully documented, and the description adds no syntax or constraint detail beyond them. The optional 'reason' audit-log parameter is not mentioned at all in the description, so baseline 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?

States a specific verb and resource ('Pin a message in a channel or thread') plus the observable effect ('appears in the channel's pinned list'). It also names the two sibling tools that do related work, so an agent can distinguish pin from list/delete without opening any 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 an explicit when-to-use rationale ('keep an important message easy to find') and routes to alternatives by name: discord_list_pins to inspect, discord_delete_pin to unpin. Nothing about tool selection is left to inference.

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