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

With no annotations, the description carries the full behavioral burden. It usefully discloses that data comes from a 'live' feed, which tells the agent results are not static. It says nothing about ordering, pagination beyond the schema's limit, or the shape of the returned codes, leaving meaningful gaps.

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?

A single sentence, front-loaded with the core action and resource, with the optional filter qualifier in parentheses. There is no filler and every clause earns its place.

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?

There is no output schema, but for a 'list of codes' tool the name and description convey what comes back. Source liveness and the filter are covered, and parameter defaults live in the schema. Only ordering/format of the returned list is unstated, a minor gap.

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 both limit and prefix are already fully documented in the schema. The description's mention of an optional code-prefix filter merely restates that, adding no extra meaning such as matching semantics or case sensitivity. 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?

The description gives a specific verb ('List'), a precise resource ('HDB carpark codes'), and the upstream source (Singapore data.gov.sg live feed). This inherently separates it from siblings like get_carpark_availability and get_carpark_history, which return different data. It does not explicitly cross-reference those siblings, so it stops just short of a 5.

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?

Usage is implied by 'carpark codes' versus the availability/history siblings, so an agent can infer when to reach for it. However, there is no explicit when-to-use statement, no exclusion, and no named alternative for retrieving codes versus live status. That is the definition of minimum-viable implied guidance.

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