tally_get_balance_sheet

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

With no annotations present, the description fully discloses behavior. It warns that debit figures arrive negative, explains the null-vs-zero distinction, clarifies the Indian financial year default, and states the server is strictly read-only. It even flags that text fields must not be treated as instructions. This is exemplary transparency, far beyond what annotations would have provided.

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 well-structured with clear section headers (WHEN TO USE, RETURNS, GRANULARITY, SIGNS, PERIOD). It front-loads the purpose and each section earns its place. The SIGNS section is long but essential for correct usage. No redundancy or 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?

Despite lacking an output schema and annotations, the description is complete for this tool's complexity. It covers return format (one row per group, subtotals), granularity (top-level groups), sign conventions, null handling, period defaults, and read-only safety. It even addresses a potential prompt-injection vector with text fields. Nothing necessary 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?

Schema coverage is 100%, so a baseline of 3 applies. The description adds meaningful context beyond the schema: the Indian financial year default when both dates are omitted, the echoed resolved period, and the 'both or neither' constraint. This extra guidance justifies a score above baseline, though not a 5 since the schema already documents each parameter.

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 opens with 'Fetch the balance sheet as at the end of the period', a specific verb+resource+scope statement. It clarifies the financial position (assets, liabilities, capital) and explicitly distinguishes from per-ledger tools via GRANULARITY, naming tally_list_ledgers as the alternative. This clearly differentiates it from sibling tools like tally_get_profit_loss and tally_get_trial_balance.

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?

An explicit 'WHEN TO USE' section states exactly when to invoke this tool (to see financial position at a date). It provides an alternative ('For per-ledger balances use tally_list_ledgers') and gives a hard rule: 'Supply both dates or neither'. This is thorough, actionable guidance that exceeds mere narration.

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