Tanod MCP server

utilpeek: find and replace in text (literal or RE2 regex)

text_replace

Read-onlyIdempotent

Replace text literally or with RE2 regex patterns using capture groups; set a maximum replacement count to control how many matches change.

Instructions

utilpeek: Find and replace in text. To sort, dedupe or number lines use text_lines. Returns the text with find replaced: literally, or as a regular expression on RE2 only (linear time for any pattern: no backtracking, so no ReDoS; backreferences and lookaround are refused), with \1 / \g in the replacement; at most max_replacements (limit_reached reported). A pattern RE2 cannot compile is a 422 invalid_pattern (not charged). Typically under 0.5 s. Price: USD 0.001. Free: 10 utilpeek calls per IP per UTC day. The submitted text is never logged or stored.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`find`	Yes	Literal text, or an RE2 pattern (mode=regex; no backreferences or lookaround; \p{L} for letters).
`mode`	No	literal (default: find is plain text) or regex (find is an RE2 pattern).	literal
`text`	Yes	The text (at most 200,000 characters).
`dot_all`	No	regex: . also matches a newline.
`replace`	Yes	Replacement; regex mode: \1..\99, \g<name>, \\ for a backslash.
`multiline`	No	regex: ^ and $ match at line breaks.
`case_sensitive`	No	Match letter case exactly (default true); false ignores case.
`max_replacements`	No	Replace at most this many matches, first to last (1-10,000, default 10,000).

Output Schema

TableJSON Schema

Name	Required	Description
`mode`	No
`text`	No
`error`	No	Only on an error result: an object {code, message}, or the reason string of an x402 PaymentRequired object.
`engine`	No
`source`	No
`replacements`	No
`limit_reached`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.3.0Oct 15, 2026

TDQS

A4.6/5.0

Behavior5/5

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety bar is low, yet the description adds real behavioral context: invalid RE2 patterns yield a 422 not charged, replacements capped with limit_reached reporting, typical latency, pricing and free-tier rate limit, and that submitted text is never logged or stored. These are things the annotated schema 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.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with purpose and the alternative tool, followed by dense but relevant operational detail. It is on the long side, but nearly every clause (RE2 guarantees, error semantics, limit reporting, privacy) carries decision-relevant information rather than filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present, return values need no explanation, and the description fully covers the remaining decision points: engine choice, replacement syntax, error handling, rate limits, and privacy. Nothing an agent needs to invoke it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

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 still adds meaning beyond the schema: replacement syntax (\1, \g<name>), the RE2 no-backreference/lookaround constraint, and the observable limit_reached behavior tied to max_replacements, which the schema does not mention.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Starts with a specific verb+resource ("Find and replace in text") and immediately scopes it to literal or RE2 regex, then names the sibling text_lines for the adjacent line operations. An agent can distinguish this from text_lines without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly routes the agent away: "To sort, dedupe or number lines use text_lines." That is a concrete when-to-use-the-alternative statement. It doesn't enumerate other boundaries (e.g. vs diff_text or text_extract), but the primary sibling collision is resolved.

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

Deploy Server