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

Annotations already declare readOnlyHint=true, openWorldHint=false, destructiveHint=false, so safety is covered. The description adds real behavioral context beyond that: the success path returns a card tool/input plus answer_line, and the failure path reports the check that stopped it plus the skill slug. With an output schema present, describing return shapes is somewhat redundant, keeping it from a 5.

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 core action and the exclusions, and the success/failure bullet structure aids scanning. The negative enumeration is dense and slightly long, but each clause maps to a real routing decision, so little is wasted.

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 read tool with an output schema and readOnly annotations, the description covers purpose, exclusions, workspace scoping, conversation_id usage, and failure semantics. Nothing an agent needs 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?

Schema coverage is 100%, so the baseline is 3. The description earns above baseline by adding cross-parameter guidance the schema does not: call directly when the token authorizes one workspace, and pass workspace_id only when several are authorized. This disambiguates the workspace_id trigger condition in a way the schema text only partially conveys.

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 specific verbs and resources: measures runway, cash position, or average monthly burn as it stands now, running every check the underlying skill performs. It sharply distinguishes itself from scenario/forecast tools and from explanation requests, so an agent can route correctly against siblings like well_render_runway or well_get_computed_figures.

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?

Explicitly enumerates when NOT to use it (no forecast, no scenario, no past period, no single account/category, no named company, no explanation) and gives a routing rule for workspace calls. This is a genuinely useful when/when-not statement rather than implied usage.

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