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

Annotations already declare readOnlyHint=false and idempotentHint=true, but the description adds real substance on top: the idempotency key is product+directory, repeats update rather than duplicate, nothing is ever deleted, and it is account-scoped requiring the MCP_API_KEY bearer token with a confirmation prompt before writing. That is exactly the auth/write semantics the annotations cannot express.

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 action and its consequence, then the status vocabulary, then the non-submission caveat and auth note. Roughly 100 words with no filler, though the status-value list is stated twice (it also appears verbatim in the schema).

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 write tool with five optional-ish params, no output schema and partial annotation coverage, the description covers everything an agent needs: purpose, effect on sibling tools, idempotency semantics, non-destructiveness, auth requirement, and a confirmation expectation. Nothing material is left to inference.

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; the description earns an extra point by defining the three status values in behavioral terms ('done or live', 'waiting on their review', 'turned down') and by explaining the composite idempotency key product+directory, which tells the agent how those two arguments interact. The product parameter itself is never mentioned, so it stops short of a 5.

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 uses a specific verb+resource ('Record that one of your tracked products has been submitted to a directory') and immediately names its downstream consumers, check_submission_readiness and generate_submission_kit, making the boundary with those siblings unambiguous.

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 states exactly when to call it (after you've submitted to a directory), what it prevents (re-submitting the same place twice), and includes a hard exclusion: 'This does NOT submit anything anywhere; it only records what you did.' That disambiguates it from generate_submission_kit without the agent opening a schema.

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