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

Annotations already cover the safety profile (readOnlyHint=true, idempotentHint=true, openWorldHint=false), so the bar is lower, and the description adds real value by disclosing the return shape: per-entry protocol cells, the full column-value set, evidence, and conditional signature. With no output schema, that payload disclosure is the main behavioral contribution; it stops short of mentioning limits, pagination, or behavior for a non-existent row.

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 core payload enumeration is front-loaded in one dense sentence followed by a short routing directive, and given the absence of an output schema the field list largely earns its place. It is a run-on enumeration, though, and the long parenthetical of column values is heavier than strictly necessary.

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 tool with nested row identification and no output schema, the description is close to complete: it covers the returned payload, the signed/unsigned condition, and step numbering from 1. It omits error behavior (missing row, ambiguous itemId/atOrder) and any result-size or pagination caveat, which are the remaining gaps.

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 100%: documentId, itemId and atOrder are all documented in the schema, including the 'pass one' constraint and the [[row N]] anchor meaning of atOrder. The description adds no format, default, or validation detail beyond that, so the 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?

States a specific verb ('Read') and a precisely scoped resource ('a bound Test Plan row'), then enumerates the exact contents (plan, columns, entries, TraceID, evidence, signature, steps) so the agent knows what it gets back. It also names the sibling traceable_test_plan_entry, making it distinguishable from the other ~24 traceable_* tools.

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 single directive 'Use it before traceable_test_plan_entry' gives one concrete sequencing cue, which is useful workflow context. However, it offers no when-not guidance and does not distinguish this read from other read paths (traceable_doc_read, traceable_grid_cell) or explain the itemId-vs-atOrder choice for locating the row.

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