decode_state_code

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

Annotations already declare readOnlyHint and idempotentHint, so safety is covered. The description adds behavioral details beyond annotations: it can accept either a two-digit code or a full GSTIN with prefix, and it returns a standard envelope containing metadata. This is useful context without contradicting the annotations.

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?

The description is compact and front-loaded. The main purpose appears in the first sentence, with a usage hint, argument example, and return note in brief structured sections. Every sentence contributes information without unnecessary detail.

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 single-parameter, read-only tool with an output schema and safe idempotent annotations, the description covers the input formats, what data comes back, and when to use it. The output schema handles the return structure, so describing the envelope as 'standard' is sufficient.

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?

The schema already covers the parameter with a description of '2-digit state code or GSTIN' and length constraints. The description adds concrete examples ('27' and '27AAPFU0939F1ZV') and clarifies that GSTIN prefixes are accepted, enriching the semantic understanding of the value parameter beyond the raw schema.

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 uses a specific verb 'Decode' with a precise resource: Indian GST state code metadata, and specifies the two accepted input forms (two-digit code or GSTIN prefix). It clearly distinguishes itself from siblings like validate_gstin and decode_pan_type by stating it returns canonical state name, abbreviation, capital, and GST zone.

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 explicitly states when to use the tool: 'Use when you need canonical state name, abbreviation, capital, and GST zone mapping.' However, it does not explicitly mention alternatives or exclusions, such as choosing validate_gstin for validation instead of decoding.

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