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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false), and the description adds genuinely non-schema context: authentication/plan requirement, the authoritative source (travel.state.gov), and a not-legal-advice caveat. It stops short of disclosing behavior for invalid months or how missing/future bulletins are handled.

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 compact sentences with no filler, leading with what the tool returns before the prerequisite and source notes. Every sentence carries distinct information.

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?

An output schema exists, so return-value documentation is unnecessary, and the auth/plan requirement plus source are stated. Minor gaps remain: no guidance on valid category values or behavior for months not yet published, which for a lookup-by-key tool an agent would want to know.

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% — month format/pattern, chart enum, country, and category are all documented in the schema itself. The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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: retrieves a monthly Visa Bulletin final-action or dates-for-filing chart entry. The chart/category/country parameters make the scope clear. It does not explicitly differentiate itself from siblings get_visa_bulletin_dv or get_visa_bulletin_notes, so an agent must infer the split.

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?

It gives a real prerequisite (sign-in at immigrationlayer.com/login and an active plan), which is actionable. But it never says when to choose this tool over get_visa_bulletin_dv or get_visa_bulletin_notes, which is the main selection question for an agent facing four bulletin-adjacent siblings.

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