baseline_variance

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context: the baseline source priority order, the labeling of P6 Planned Start/Finish as not a true baseline, and the positive/later-than-baseline sign convention. This goes beyond what annotations provide.

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 a single dense paragraph that front-loads the core output (variance in working days, sort order) and then explains the baseline source priority. Every sentence earns its place, though the baseline source explanation is somewhat long and could be split for readability.

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 read-only analysis tool with no output schema, the description covers the key output (variance per activity, project finish variance), the unit, the sort order, and the baseline source resolution. It doesn't explain the limit or project parameters, but the tool is still callable with just path. The description is complete enough for an agent to select and invoke the tool correctly.

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 0%, so the description must compensate. It explains the meaning of baseline_path (a baseline schedule file matched on activity ID) and the fallback baseline sources, which helps with the baseline_path parameter. However, it doesn't explain path, limit, project, or baseline_project semantics beyond what the schema names provide. The description adds some meaning but not enough to fully compensate for 0% coverage.

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 states a specific verb ('variance of every activity against a baseline'), the resource (activities), the unit (working days), the sort order (worst finish variance first), and the additional project finish variance. It clearly distinguishes itself from siblings like schedule_summary or compare_schedules by focusing on baseline variance.

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?

The description explains the baseline source priority order (baseline_path, MS Project Baseline 0, P6 Planned Start/Finish), which tells the agent when the tool will use which source. It doesn't explicitly name alternative tools to use instead, but the context is clear enough for an agent to know when to invoke this tool.

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