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

Annotations already declare read-only, idempotent, non-destructive behaviour, so the bar is lower; the description still adds substantial non-obvious behaviour: part months prorated by calendar days, amounts in words in the Indian system, Hindi and other Indian scripts, a revenue stamp box for cash above Rs 5,000, and a landlord PAN line above Rs 1,00,000. It also discloses the limit that no PAN is accepted, which prevents an agent from assuming tax handling.

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?

Everything is front-loaded — purpose, then inputs, then behaviour, then exclusions — and every clause carries information. It is one dense run-on with semicolon lists, which makes it harder to scan than it could be, but no sentence is filler.

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 16-parameter generator with an output schema already defined, the description covers the non-obvious edges an agent needs: part months, mid-year rent changes, cash-stamp and PAN thresholds, script support, and what it refuses to do. Nothing required to invoke it correctly is missing.

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?

With 100% schema coverage the baseline is 3, but the description adds routing meaning: it names the fields to populate (monthly_rent, tenant_name, landlord_name, property_address, financial_year or from/to, rent_changes, payment_mode) and demotes details to a fallback for pasted text, which the schema alone does not say as clearly. Minor added value remains around precedence between monthly_rent and rent_changes, though the schema covers it.

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 artifact ('generate rent receipts for HRA... as a print-ready PDF'), plus the exact output shape (one receipt per month, 2 or 3 per A4 page plus a summary page) and the India/HRA ACCOUNT scope. An agent knows precisely what it produces without opening the schema.

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?

Opens with an explicit trigger ('Use this when the user wants rent receipts for HRA'), names the two inputs that define the period (financial_year or from/to), and closes with explicit exclusions: 'Do not use for rent agreements or for tracking unpaid rent.' It also states its own scope limit (does not compute HRA exemption or tax) and that details is only a fallback.

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