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

Annotations already declare write/destructive/idempotent semantics, so the bar is lowered. The description adds genuine value beyond them by clarifying that only passed fields are sent while those fields are overwritten, plus the PUT /deals/{id} endpoint. It omits permission/auth requirements, but the partial-overwrite nuance is a meaningful disclosure.

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?

Three tight sentences, front-loaded with the "WRITE:" operation label and ending with the endpoint. The overwrite caveat is placed before the URL so critical semantics come first; nothing is redundant.

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 12-parameter write tool whose schema has full coverage and whose annotations carry the safety profile, the description covers operation type, partial-update behavior, and endpoint adequately. No output schema exists, so return values need not be explained; only auth/permission notes are absent.

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 fully documents all 12 parameters and the baseline is 3. The description adds only a light hint by naming stage and won/lost as examples, without new syntax or format detail.

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 ("change fields of one deal") and reinforces it with concrete examples (move stage, mark won/lost), which cleanly separates it from create_deal and get_deal. It stops short of explicitly naming siblings, so 4 rather than 5.

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 update examples imply typical use cases but there is no explicit when-to-use/when-not-to-use guidance or direction to alternatives (e.g., create_deal for new records). Usage is inferable rather than stated.

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