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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavioral context beyond that: the output is step-by-step with exact UI button names, and the no-argument path returns an enumeration rather than erroring. It doesn't discuss guide length or what a listing entry contains.

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?

Two sentences, zero filler. The primary behavior is front-loaded and the fallback case follows immediately, so the agent reads the decision-relevant facts first.

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 one-optional-param read tool with no output schema and annotations covering safety, this is nearly complete: the agent knows what it gets, what shape it takes, and what happens with no argument. Minor residual gap is guide length/coverage of the 11 tasks, which is low stakes.

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% with the enum's own description already saying "Leave out to list them all." The description's "Without a task, lists the tasks" restates that, adding almost nothing beyond the schema; the enum values themselves carry the task semantics. Baseline 3 applies.

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?

Names a specific verb+resource (fetch step-by-step instructions for one task on iomarkets.ai) and states both operating modes: a single task guide, or a task list when no task is supplied. That dual-mode framing makes it clearly distinct from siblings like get_overview or explain_term without needing to name them.

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?

"Without a task, lists the tasks" tells the agent exactly how to use the omittable parameter as a discovery path, and "for one task" frames the primary case. It stops short of naming alternatives (e.g. explain_term for glossary lookups) or stating when not to reach for this tool.

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