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

The readOnlyHint annotation already establishes safety, so the bar is lower. The description adds useful behavior context: pins are operator-controlled, usually containing rules/links/standing context, and reading them is cheaper than history. This goes beyond the annotation without contradicting it.

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?

Two concise sentences carry the purpose, content expectations, and cost comparison with no wasted words. The use case is front-loaded and the alternative is mentioned efficiently.

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, one-parameter read operation with a readOnlyHint, an output schema, and clear sibling context, the description covers what pins are, when to use them, and why they are preferable to history. Nothing essential is missing.

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% and the single channel parameter is already well described in the schema, including the leading-# flexibility. The description adds no additional parameter-level detail, 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 title supplies the verb 'Read' and the resource 'pinned messages', and the description explains what pinned messages typically contain (rules, links, standing context). It also distinguishes itself from freeq_history by noting it is cheaper, so an agent can tell it apart from at least one sibling.

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 explicitly says to use this when you want to know what a channel is for, and positions it as cheaper than reading history. It does not, however, give explicit when-not-to-use guidance or compare against freeq_search and freeq_verify.

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