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

Annotations already cover readOnly, idempotent, non-destructive and closed-world, so the bar is lower, yet the description still adds real behavioral context: 'Free' (no cost/paid path, unlike submit_paid_line) and 'It does not send anything to anyone' (no outbound side effects). It also discloses that audience=human changes output shape to a one-liner. It doesn't state the return format (plain text vs structured), a minor omission.

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?

Four short sentences, front-loaded with what the tool returns before the when-to-use clause. Every sentence carries information, though the title line duplicates the first clause of the description slightly.

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?

With no output schema, the description carries the burden of describing the return value, and it does: a short copy-paste note containing the MCP URL, steps, and docs link, with a one-line variant for humans. Annotations cover safety. The only gap is not stating the serialization format of the returned note.

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 description coverage is 100%, so baseline is 3. The description still adds meaning beyond the schema: audience=human is characterized as 'a one-line version for a person', and hash/index are implicitly explained as inputs that produce a linked passage in the note, which the schema describes only tersely.

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 ('Get') and resource ('a short copy-paste note that explains Stint and how to join'), then enumerates its contents (MCP URL, steps, docs link). This is clearly distinguishable from siblings like share_card or read_spec, and the 'does not send anything to anyone' clause further separates it from share_card's implied sharing behavior.

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 trigger: 'Use it when your user or another agent asks how to take part.' That is a clear usage context with a named actor. It stops short of naming an alternative tool to prefer or an explicit when-not condition, so it lands just below the top tier.

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