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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered; the description usefully adds return semantics (continuous-intake visas return 'open'; round-based programmes return last round and cutoff score). It does not discuss freshness, caching, or error behavior when a visa_id is unknown.

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?

Purpose and guidance are front-loaded in one sentence, and the return contents follow. The closing sentence on continuous-intake is useful but the prose is dense enough that one more sentence would have been bloat.

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 enumerates the returned fields (status, last round, cutoff score, next expectation, official source), which is the needed compensation. Risk/edge handling (stale data, unknown visa_id) is the only gap for a lookup tool.

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% and the single visa_id parameter is already documented with an example and a pointer to transita_match_visas/transita_list_visas. The description adds nothing about the parameter beyond 'a single visa pathway', 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?

Specific verb+resource: 'Check the live intake status of a single visa pathway', followed by the exact return payload (open/closed, last round, cutoff score, expectation, source). It clearly separates this from transita_visa_details by scope: one live status field set versus full details.

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 prescriptive trigger — 'Call this before recommending a pathway so you never send a user toward a closed or paused programme' — which tells the agent exactly when in the workflow to use it. It does not name a sibling alternative or state when to skip it, so it stops short of full when/when-not coverage.

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