pin_message

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

With no annotations, the description fully discloses behavioral traits: system-level notification, visibility to all participants, no admin privileges needed, automatic replacement of previous pin. It covers all key behavioral aspects without contradiction.

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 and well-structured. The first sentence front-loads the primary purpose and effect. Each subsequent sentence adds unique value without redundancy. The final note about not using for personal bookmarking is a useful exclusion.

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 the absence of annotations and output schema, the description covers all necessary aspects: purpose, parameter usage, behavioral effects, constraints, and alternatives. It is fully self-contained and leaves no gaps for correct tool invocation.

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?

Although schema coverage is 100%, the description adds significant meaning beyond the schema. It explains the mutual exclusivity of recipient and group_id, and clarifies that target_author and target_timestamp come from get_conversation. This context is essential for correct parameter usage.

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 clearly states the verb 'Pin' and resource 'message in a DM or group conversation', and distinguishes from sibling tools like unpin_message by specifying its purpose of highlighting important messages for all participants. It also explicitly differentiates from personal bookmarking.

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 explicit guidance on when to use (highlight important messages) and when not to (personal bookmarking). It explains the constraint of only one pin per conversation and gives clear instructions on parameter selection (recipient vs group_id). It also directs users to get target_author and target_timestamp from get_conversation.

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