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

Beyond the annotations (which already declare readOnly, idempotent, non-destructive, closed-world), the description discloses real operational traits: card-only rendering with no photos, automatic layout with no manual dragging, a hard 500-person cap, and the fact that unsupported scripts or emoji produce an input error rather than a degraded output. That font/error constraint in particular is the kind of failure mode an agent cannot get from the schema.

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?

Front-loaded with the trigger condition and dense throughout; the limits-and-exclusions sentences each carry distinct information. It is a single run-on paragraph, though, and the input/output mechanics, styling options, limits and exclusions would be easier to scan as separate lines.

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 5-parameter, no-required-parameter generative tool with nested people records, the description covers input forms (inline list or file), the full option surface (paper sizes, color_by, orientation), output artifacts, and hard limits. An output schema exists, so it correctly does not re-explain return values.

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 the baseline is 3; the description still adds value by stating the 2-500 people range, that manager references resolve by id or name, that department drives the color_by choice, and that CSV columns are matched case-insensitively. It does not, however, reconcile the stated 500-person ceiling with the schema's maxItems of 1000, leaving the true cap ambiguous.

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 ('create an org chart') and enumerates the user-phrasings it covers (org chart maker, company hierarchy chart, team structure chart), plus what input it consumes (a reporting list or CSV/XLSX) and what it produces (SVG and PDF). No sibling tools exist, so no differentiation is needed.

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...') and closes with explicit exclusions ('Do not use for family trees, flowcharts or seating charts'). Both halves of the routing decision are stated outright, leaving nothing to inference.

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