memory_read

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

With no annotations, the description carries the full burden. It usefully discloses the default file, the allowed file set, and the truncation behavior of tail. It does not state that the operation is read-only/non-mutating (only implied by the verb), nor what happens on a missing file, so the safety profile remains implicit.

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?

A compact three-clause line: purpose first, then filename semantics, then tail semantics. No filler; each clause adds information an agent 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?

An output schema exists, so return values need not be described, and both of the two parameters are semantically covered. The only real omission is sibling routing (read-by-name vs memory_search), which matters for a 2-param read tool but is a minor gap.

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 0%, so the description must compensate and largely does: it supplies the default for filename, enumerates the valid values not present in the schema, and explains that tail>0 returns the last N lines with a rationale (token savings). Only minor gaps remain (e.g. behavior when tail exceeds file length).

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 (读取/read) and resource (记忆文件/memory file), and enumerates the concrete file set (FACT.md, SOUL.md, USER.md, JOURNAL.jsonl). It is clearly distinguishable in kind from memory_update/memory_append/memory_search, though it never names those siblings explicitly.

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 does give a genuine usage rule for one parameter ('tail>0 时只返回最后 tail 行（读大文件时用，省 token）' — use when reading large files to save tokens), which is more than nothing. However it gives no guidance on when to pick this tool over memory_search or the other siblings, so routing is left to inference.

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