kia_charge_targets

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

Annotations already provide readOnlyHint=true, so the 'Read-only' statement is redundant. However, the description adds valuable non-annotation context: it reveals the return contents (target state of charge per plug type, AC and DC) and a provenance claim ('Verified live against a real vehicle'). This is meaningful for an agent because there is no output schema.

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 short sentences with no fluff. The core action and resource are front-loaded, the output detail is compact, and the read-only note and verification claim each add relevant context. Every sentence 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?

For a simple single-parameter read tool, the description is complete: the only parameter is fully documented in the schema, read-only behavior is declared in both annotations and description, and the output is described (charge targets per plug type) even though no output schema exists. An agent has everything needed to call it correctly.

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 vinKey property is well-documented ('Vehicle key... Not the VIN'). The description adds no parameter-level detail, but because the schema already fully covers the parameter semantics, the baseline of 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 ('Read'), a specific resource ('EV charge targets (`evc/gts`)'), and the output shape ('target state of charge per plug type... AC, one for DC'). Clearly distinguishes from sibling write tools like kia_start_charge, kia_stop_charge, and kia_set_charge_limits by emphasizing read-only.

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 gives clear context: this is a read operation for charge targets and explicitly says it 'makes no changes'. This implicitly excludes using it to modify targets, and the read-only framing separates it from write siblings. It does not name an explicit alternative tool or state when-not-to-use it, so it stops short of a full 5.

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