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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description adds genuine non-schema behavior: the modeling assumptions (top federal rates, no state tax or AMT) and a provenance/limitation caveat ('Illustrative model, not tax advice'). That is meaningful context beyond 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?

Three sentences, front-loaded with what is computed, then scope limitations and a reference URL. Every sentence carries weight, with only the model-provenance URL being marginally extraneous.

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 13-param, no-required-argument calculator with no output schema, the description communicates what the three output figures are and the key modeling caveats. It stops short of describing the response structure or units, which is the main remaining gap, but it is broadly complete for correct invocation.

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 each of the 13 parameters is documented with defaults and constraints, so the baseline is 3. The description adds no per-parameter semantics beyond implying a 'sale price' input; the schema does the heavy lifting.

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 three specific computations (83(b) deadline/tax, QSBS Section 1202 federal savings, Delaware franchise tax under both methods) with a clear verb+resource. This is plainly distinguishable from the sibling calculators like calc_burn_multiple_runway or calc_safe_dilution 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?

Usage is implied by the tightly scoped purpose (compute these three tax figures), and the scope caveats ('federal tax only') help the agent decide if it fits. However there is no explicit when-to-use/when-not framing or routing to alternatives, so it stays at implied-usage level.

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