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

Annotations already declare readOnly, idempotent and non-destructive behavior. The description adds output context with 'Returns the verdict for each school and the reasoning' — valuable since there is no output schema — though it does not mention any limits or input-validation constraints.

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, front-loaded sentences that are easy to scan. The leading 'Halal or Not.' brand fragment slightly duplicates the title, but overall the text is efficient with little waste.

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 read-only lookup with fully described parameters and no output schema, the definition is nearly complete: it names the resource, gives examples, and sketches the return shape (per-school verdict plus reasoning). The only gap is the absence of any sibling routing or context-enum guidance.

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 parameters are already documented; the description's ingredient examples reinforce the 'name' parameter but add nothing new. The 'context' (food/cosmetic) parameter is not mentioned at all in the description, so the schema carries the full burden there.

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: 'Explain one ingredient or E-number', with concrete examples (E471, carmine, prawns, whey). The singular 'one' implicitly distinguishes it from the bulk halalornot_check_ingredients, but no sibling is named. Clear purpose, no explicit differentiation.

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: explain a single ingredient or E-number. There is no explicit when-to-use guidance, no exclusions, and no mention of the adjacent halalornot_check_ingredients (bulk) or halalornot_explain_schools alternatives, leaving routing to inference.

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