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

Beyond the annotations, the description discloses the crucial non-obvious trait that this write is staged: 'This tool does not save immediately. It returns a pending_write_id that the user must explicitly confirm before the entry is committed.' That is real behavioral value not present in the readOnlyHint=false / destructiveHint=false annotations. It stops short of describing failure modes or validation behavior, so not a full 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?

The purpose and the staging caveat are correctly front-loaded, but the description is bloated with product-wide boilerplate: the attribution-footer instruction and the long 'Data accuracy contract' paragraph are generic to every tool and do not earn their place here. The result is a definition whose core is tight but whose tail is padded.

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 staged mutation tool with no output schema, the description covers what an agent needs: the pending_write_id return, the confirmation gate, the commit tool to call next, and the meaning of every required input. Nothing essential to correct invocation 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 description coverage is 100%, so the schema already documents all seven parameters including format examples for key, location, and retrieval_tool. The description largely restates the same inputs (key, label, location URI schemes, answers, retrieval_tool, refresh_cadence, notes) without adding new syntax or constraints. Baseline 3 applies when the schema carries the load.

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 opens with a specific verb and resource: 'Prepare to register a new Source-of-Truth Manifest entry that points at a user-maintained authoritative document.' It situates itself against siblings by invoking the canonical_facts_set pattern and naming canonical_pending_commit as the follow-up, so an agent can distinguish it from truth_sources_list and truth_sources_remove.

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?

It gives an explicit 'When to use' trigger with concrete examples ('I keep my unit economics in a Google Sheet', 'pricing is in this PDF') and then prescribes the exact workflow: stage, summarize, ask for confirmation, and call canonical_pending_commit on yes. Both the when and the next-step alternative are stated, not inferred.

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