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

No annotations are provided, so the description carries the full behavioral burden. It reveals the mutation direction (appended to the end, not replacing) but says nothing about permissions, formatting handling, behavior when the id is not found, or what the response contains.

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?

One front-loaded sentence with zero filler; the mutation target and append semantics come first. It is efficient but so terse that it leaves no room for the behavioral context a no-annotation mutation tool needs.

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?

With no annotations, no output schema, and only 33% schema coverage, the description should explain return value, error behavior on a missing note, and whether a separator is inserted. None of that is present.

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 33%: only 'workspace' is documented in the schema, and it is described well. The description adds real meaning for 'content' by specifying Markdown, and 'existing note' implies id is a note identifier, partially compensating for the undocumented id parameter.

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?

A specific verb ('Add') plus resource ('Markdown content ... existing note') with the append-to-end semantics made explicit, which distinguishes it from update_note or create_note. It stops short of naming those siblings directly, so it is clear but not fully differentiated.

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?

'existing note' implies the precondition that the note must already exist and that this is additive rather than replacing content, which is enough to choose it over create_note. However, it never states when to prefer this over update_note, nor any exclusions or prerequisites.

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