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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered and the description stays consistent with it ('Read-only; the tool writes nothing'). It goes beyond the annotations by clarifying the division of labor — the host agent performs code edits, verification, and commit — and by naming the artifacts loaded and returned, which is genuinely useful behavioral context.

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-loads the phase, action, and read-only nature, then covers sequencing and parameter relationships with no filler sentences. Slightly dense in the final parameter-relationships clause, but every sentence carries information.

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?

Output schema exists, so return-value documentation is not required, yet the description still names what comes back. Combined with sequencing, the alternative tool, and parameter provenance, an agent has everything needed to invoke it correctly in the workflow.

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, but the description adds cross-tool provenance for taskId ('from the task returned by vdd_get_next_task', format TASK-###) and a constraint for projectRoot ('must match the root used by earlier phases'). That is real meaning beyond the schema's own text.

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 ('Prepare one task for implementation') and enumerates exactly what it loads (constitution, spec, plan, contracts) and returns (implementation instruction plus impact-chain commit-message format). It is clearly distinguishable from siblings like vdd_get_next_task and vdd_inspect.

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?

Gives explicit sequencing ('Run one task at a time, after vdd_get_next_task') and an explicit exclusion ('for read-only inspection of tasks use vdd_get_next_task instead'). Nothing about when to reach for this tool versus an alternative is left to inference.

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